When I was planning my spring hunt with Chris Bohnhoff last year, we made a dinner to be part of the video. As luck would have it though, the day was rainy and the lighting inside wasn't up to scratch, so our dinner didn't make the footage.
We had a risotto of fresh morels, spruce cured salmon with a fiddlehead salad and lamb loins marinated in wild peppermint. The dinner was just fine, but what I put the most work into was the dessert. I wanted to make something that represented the farm that's taught me so much about the wild foods where I live.
I dreamed up a wild rice sponge rolled around a mousse of knotweed from the garden, frosted with a buttercream sweetened with the farm's maple syrup and garnished with wildflowers and herbs from the prairie on top of the nearby bluff. It took four or five tries for me to be happy with it, but in the end it was worth it. It's a dessert, and an expression of what I've come to love about the farm.
The cake itself is really not too difficult, the wild rice sponge and mousse are just two easy recipes combined and the frosting/garnishing are optional, but pretty. Here's how I made it.
To show a little of the possibilities. I worked on a simpler version with rhubarb sauce, since it and the knotweed are distant cousins and taste eerily similar.
I've listed the 3 sub-recipes for the cake below. To assemble it or something like it, you'll want to make the cake first, then stuff with the mousse, roll and chill to set. Before serving, frost it with the butter cream, then decorate with the flowers (if using) just before serving.
Special thanks to Chris Bohnhoff for shots of the assembly and the frosted cake.
Wild Rice Sponge Cake
Equipment
- Stand mixer or beaters
Ingredients
- 4 large eggs
- ½ cup white sugar
- ¾ cup wild rice flour
- 2 ounces ½ stick unsalted butter
- Pinch of salt
- 1 teaspoon of equal parts toasted and ground: cinnamon nutmeg, allspice, and cloves (optional)
- ½ teaspoon powdered ginger
- Pinch of salt
Instructions
- Preheat an oven to 350. Melt the butter. In a stand mixer or bowl, beat the eggs with the sugar until light, fluffy, and doubled in volume, fold in the spices, salt, and wild rice flour, along with the melted butter. Line a cookie sheet with parchment and oil it to prevent sticking. Pour in the batter and spread until smooth. Bake the sponge for 12 minutes, then allow to cool for a minute or two. lay a towel on a flat surface, then, very carefully lay the sponge cake on top, removing the parchment. Roll the sponge cake up in the towel to help it form the jelly roll shape it will become. If it tears a bit, don't worry, you can cover it up with butter cream later, or just slice as-is, it won't be too noticeable.
Notes
Knotweed Mousse
Ingredients
- ⅓ cup Sugar or maple sugar
- 1 lb Japanese knotweed shoots
- 4 leaves gelatin 1.25 tablespoons powdered gelatin can be substituted
- 3 egg whites whipped until stiff with ⅛ cup white sugar
- 2 tablespoons roughly chopped wild peppermint optional
Instructions
- Clean the knotweed shoots and cut into pieces. Cook with the sugar on medium high heat until the stems have started to break down and are soft, about 15 minutes. The mixture should be thickened and you should be able to see the pan through the mixture when you drag a spoon through it.
- Puree the knotweed in a blender until very smooth, then cool in a covered container and chill.
- Bloom the gelatin in ice water until soft, then gently heat the knotweed puree and whisk in the gelatin until dissolved. Chill the mixture, whisk to relax the gelatin, then fold in the beaten egg whites and wild mint. Chill again, covered with plastic wrap until ready to use/serve.
Notes
Maple Buttercream
Equipment
- Stand mixer or beaters
Ingredients
- ½ cup maple syrup
- 3 egg yolks
- ½ lb unsalted butter diced ½ inch
- Pinch of kosher salt
Instructions
- Heat the maple syrup, bring to a simmer and keep warm. Beat the eggs, slowly drizzling in the still warm maple syrup, turning the speed to high if you're using a stand mixer. Make sure to allow the maple syrup to drizzle down the bowl so that it doesn't cook the eggs.
- When all the maple syrup is added, add the butter a couple pieces at a time, until it is all incorporated and the mixture is smooth.
- Finally, add the salt, then transfer to a container. Keep the buttercream at room temperature until you're ready to frost the cake. Butter cream can be frozen for months and then allowed to thaw at room temperature and whipped to fluff it up lightly before using.
Carla Beaudet
Decided to do this with some of the knotweed this year. The sponge cake and the mousse came off without a hitch, but the buttercream? A soupy mess of butter bits and egg. I did heat the maple syrup, but apparently not enough to temper the eggs. To rescue the batch, I did a bunch of crazy things: added a tsp. of cornstarch, added about 1/2c. powdered sugar. Then, figuring it was the eggs needed to set a bit, dashed back and forth between the microwave and the mixer a few times, trying not to heat things up too much. It may have worked? The mixture has finally become homogeneous and creamy, but is too soft to be called frosting, so it's having a sit in the refrigerator while I clean up everything except the stand mixer... Note: in the kitchen, baking is my area of least experience.
Alan Bergo
Thanks Carla. This is an old recipe that needs some love. An important thing I neglected to put in there is that the maple syrup needs to drizzle down the side of the bowl so it doesn't cook the eggs. And, I sabotaged you as there's a typo too: it should be only yolks, not whole eggs. I'm making a note to give it a test run this week. Sorry about that.
Carla Beaudet
As it turned out, freezing separated the butter again. I gave up and started over, combining the eggs and maple syrup (I had 3 egg yolks from making the mousse and I used them plus 1 whole egg) and bringing that mixture (no extra water; there's water in the syrup) to 165F on a double boiler, and let it go for a full 10 min in the stand mixer before adding room-temp butter to it. Worked like a charm. I think temp control is the main key to French buttercream. I'll email you a pic.
Alan Bergo
Thanks Carla. Glad you found a workaround.
N
Hi! Wondering if the sweetened knotweed puree recipe is still available anywhere? The links are broken and I don't see it featured on this website anywhere else. Thanks so much! Can't wait to cook and consume my most hated garden enemy 🙂
Alan Bergo
Hi Natalie, I added it back into the recipe. Thanks for letting me know that wasn't listed.
Amanda Evans
Just tried this recipe and it turned out great! But I was a little confused about the cake recipe because the ingredients call for butter but there's no butter in the cake?
Alan Bergo
Shoot! You're right. Thanks for catching it--I'm human over here, and this is a pretty old recipe of mine. The butter is just to add a little moisture, and as you found out, it's ok if it isn't included. Lmk if you need any help trouble shooting anything else. A