Steeped in the wisdom of centuries of Celtic kitchen tradition, this is a St. Patrick’s Day classic that is as Irish as a red-headed leprechaun. Maybe not, but that is what is going to pop up on Google indexing. In reality, it is nothing more or less than my most researched and refined preparation to date. It took some work. I mean it really, really, took work, so I am going to put it out here in no uncertain terms – you need to try this. I can at a bare minimum guarantee you have never, ever had anything like it. And there is no filmjölk in it, which should cheer up a fair number of you.
I responded to a recent challenge by Food Bloggers of Canada to create a St. Patrick’s Day inspired recipe, incorporating the required theme of “green”. Recently my brain had been
addled preoccupied by several dishes that existed only in draft form; rough blueprints for delicacies that I had resolutely decided I would build. The problem I had was that neither of them were obviously green, and beyond that did not seem to have any miraculous or stirring quality that would mark them as contest worthy. As I often do after hours of rigorous analysis and planning, I succumbed to panic and decided to chop and stitch them together like a bastard Irish Frankenstein. Of course, you can only get so far on panic, so fear was slowly replaced by reflection, optimism, and finally, confidence. Mostly false confidence, tempered with enough ignorance to get the creativity machine in gear.
All I knew was that I wanted chocolate, and I wanted tarragon. Liquorice type flavours have become a fetish of the moment for me, and I knew that chocolate and tarragon should be able to come together alluringly. The question was how. Well, it took a lot of research into published recipes, aroma theory, chemistry, and above all – tons of testing.
My inspiration for the white chocolate mousse was from Heston Blumenthal and Hervé This. I had already found that, contrary to a dark chocolate mousse, trying to make a white one with cream never gave a decent result. The mousse was always too sweet and the cream was overpowering to the point that I was beginning to believe I needed to rethink the entire project. Happily, the Blumenthal/This mousse foregoes cream entirely, consequently enhancing the natural taste of the white chocolate. Still, my feeling was that the finished product was lacking in bitterness. I tried citrus rinds, Angostura bitters, and was beginning to lose hope when I discovered a similar recipe online that incorporated Earl Grey tea. Playing with different types of teas (six in total!) yielded a better mousse, but all was not entirely well. It was too smooth, too dense, and it lacked a real punch. When the dust, sugar, and salt settled I opened the fridge door three days later to find a light-as-air white chocolate mousse with a dazzling flavour profile and salty finish. It is paired with a sweet, fragrant, homemade tarragon liqueur and is a simply amazing dessert that would be worthy of any friend you might like to share it with.
White Chocolate, Darjeeling, and Salted Caramel Mousse
200 g white chocolate
70 mL strong green tea (I settled on Darjeeling)
2 egg whites
20 g salted caramel pieces
Prepare a large bowl filled with ice, or in the case of St. Patrick’s Day in Canada use a cost-cutting alternative – snow. Fill a large saucepan to 1/3 with warm water and place on the stovetop to simmer at low heat. Weigh the white chocolate into a metal or glass bowl that is slightly smaller than your bowl of ice and place on top of the hot water inside the saucepan. It is important to melt the chocolate in a controlled fashion at this point, so do not hit the boil button and waste all that expensive cocoa goodness. Pour in the tea, and stir intermittently as it all melts together in a beige mix. While this is underway, take two egg whites and beat them until you have a nice, firm, foamy product. Put the bowl in the fridge for later. Once you are sure all the chocolate has dissolved, place over the ice and quickly whisk for your life. The important part here is to incorporate a good deal of air into the emulsion you are forming. In this case our emulsion is a mixture of oil from the cocoa butter and water from the tea, and the rapid whisking gives very small droplets of two different liquids that do not easily come back together into a runny mess. Cooling the emulsion makes this process even slower, which is why we use so much ice. You can lay down your whisk once the mixture has hardened to the point where the structure is beginning to firm up and you need to shake the mousse to get it all back into the bowl.
At this point, you have a decision to make. If you have gone mental on your whipping and believe the mousse is too hard, then you can put it back onto the simmering water, melt, and get a free do-over. If your mousse is not getting stiff at all, add a bit more chocolate, melt, and repeat the whisking over ice. Once you have a product that gives stiff peaks that do not collapse you are ready for the next step.
It is firm, but not foamy enough, so we are going to take about one third of the beaten egg whites and gently fold them into the mousse. Do not agitate it too much as this will collapse the structure of the egg whites. We only add one third of the mix because a small amount of collapsing is exactly what happens at this point since the mousse is still too firm and provides a lot of resistance. Once you have mostly incorporated the egg white go and add the remainder, again gently working them into the mix. Just before you think you are finished, add the crushed caramel pieces and continue folding until you have a homogeneous mixture with no remaining egg white visible.
Place in cups, cover, and let set in the fridge for at least one hour. Do not leave overnight or you will find that the salted caramel has started to break up and dissolve, diminishing the crunchiness that makes the dish so attractive. When serving, be imaginative – add some extra salted pieces, tarragon, liqueur, white chocolate – whatever takes you.
I actually did not have the time to go and buy the salted caramel pieces, which you can normally buy at Walmart or Bulk Barn, so I made my own. It actually only takes about 15 minutes, requires only sugar, butter, and salt, and tastes great. Here is a quick recipe.
270 g butter
200 g white sugar
1/2 teaspoon salt
Heat everything in a saucepan. If you have a thermometer, heat with intermittent stirring until about 140ºC, then pour over parchment paper on a flat surface such as a baking tray. Cool in the fridge. Done. If you don’t have a thermometer, look for a caramel colour such as in these photos, testing periodically by putting a small amount of the mix into a glass of cold water, then stirring it to see if it forms a hard ball. If it does, you are there.
The essential oils of tarragon are dominated by the liquorice odour of the molecule named estragole. As you might expect, the chemical is extremely similar to the one providing the major aromatic note in the star anise we used in the Valentine’s Day recipe, anethole. I have always been impressed as to just how pure and refined the flavour of tarragon is, and I had every hope of being able to turn the forest green herb into a bright syrup that would still retain the wonderful simplicity of its essence. I had devised a way to do this using my good friend, 94% alcohol. The advantage of using alcohol to extract the compounds from the tarragon was that I could use a relatively low temperature (room temperature), and I would be able to isolate not only the gorgeous aromas, but the striking colour as well. Most herbal syrup recipes you can find for desserts or cocktails are made by boiling herbs in water. Unfortunately, this rapidly degrades the fragile chemicals they hold, changing both flavour and colour. Why are none of these common syrups green? For the same reason that leaves go brown in the autumn; the bright green chlorophylls have been broken down by light, heat, and oxygen, and no new chlorophyll is being produced to replace them. In order to preserve them as much as possible we need to use some science.
‘Bah, science!’, you say. Would it help if I told you it was about alcohol? Alcohol has a revered place in my kitchen. When it is not in my glass it is in my mortar, being ground into every food I can get my hands on. Not necessarily because I am an alcoholic, either. No, it is more because of its incredible ability to create a friendly environment for the flavours I love. Like vodka. Alcohol, or ethyl alcohol if you like, is capable of making these chemicals soluble. So while the green chlorophyll does not want to find a home in water, it is very happy to snuggle up in alcohol. This goes for the compounds associated with aromas as well, so if you are looking for a mild method for extracting as much flavour and colour from your favourite foods then look no further than booze. Thank God for booze.
Oil is also excellent at extracting flavour, which is one reason why you fry spices. That said, I wasn’t sure that a green, greasy glob of tarragon was going to outdo my tarragon liqueur as a pairing, so I dismissed that idea pretty quickly. Still, if you are a fan of foams, you should be able to come up with a stabilised foam to serve on the mousse that would also have the deep tarragon aroma. Send me a recipe if you do. For now, here is how we make the tarragon infused liqueur.
3 large sprigs of french tarragon
100 mL 94% alcohol (or use vodka)
100 g white sugar
240 mL water
1/4 teaspoon xanthan gum
Cut up the tarragon and place it in a mortal and pestle. Add the 94% alcohol (which you can buy at the SAQ if you are in Quebec) or vodka and mash the leaves to break them up as much as you can. After a minute or two pour the extremely bright green liquid into a covered container, add the broken leaves and stems, and leave overnight in the refrigerator. This added time will aid the extraction of the colour and flavour, and placing it in an airtight container in a cold, dark fridge is the best way to preserve the chemicals responsible for the liquorice perfumed green potion we are going to brew.
The next day remove from the refrigerator. Warm 240 mL of water in a small saucepan and stir in the sugar to dissolve. When this happens, transfer to a blender and sprinkle over the xanthan gum in batches while pulsing to make sure it mixes in. Do not add all of it in one go or it will clump up and you will be blending for a long, long time. Once it is all added pour in the tarragon infusion you prepared the day before. Pulse again to mix well then set aside. You will notice a fair bit of air bubbles in the liqueur – this is normal and after about 20 minutes they should rise to the top and disappear.
Serve cold with the mousse. I saw some kiwi berries on sale at our IGA and I added them to give a citrus palate cleansing to prepare for the drink.
Let me know your thoughts. Improvements? Throw it out and start over?