Yield: 10 inch Mousse Cake
| Ingredients | Amount | Notes |
|---|---|---|
| Base | ||
| Peanuts | 60g | Chopped |
| Rice Krispies | 50g | or Reese’s Puffs (Crushed) |
| Corn Syrup | 100g | |
| Granulated Sugar | 50g | |
| Salt | 5g | |
| Filling | ||
| Whole Milk | 240g | |
| Egg Yolks (large) | 150g | About 8 yolks |
| Vanilla | 10g | |
| Granulated Sugar | 150g | |
| Salt | 2.5g | |
| Gelatin | 17g | w/ 90g Water |
| Peanut Butter | 330g | Creamy, processed version |
| Heavy Cream | 600g | Cold |
| Grape Layer | ||
| Grape Juice | 960g | Best Quality Available |
| Granulated Sugar | 75g | |
| Agar Agar | 7g | Mixed w/ Sugar |
| Salt | 3g |
Procedure:
- I recommend assembling this cake in a 10 inch Cake Pan, or better yet – Cake Ring, not a Springform pan, unless you have the means to line the inside with an acetate collar. This is entirely because of the liquid grape layer, but you can assemble it in more or less anything if you skip the grape layer, and do the chocolate ganache in the notes below.
- Line the bottom of your cake pan, with a circle of parchment, and line the inside ring with some strips of parchment. They will stick perfectly if you grease the pan beforehand. This gives us some certainty in getting the whole thing out later. Grease the top of the parchment on the bottom as well.
- Combine your chopped peanuts, Rice Krispies, and salt in a small bowl. Heat the corn syrup in the microwave until hot and pour it over the nuts and cereal. Toss it all together so it’s equally coated and sticky, then pour the granulated sugar on top and toss some more to evenly coat everything.
- Do your best to press this evenly into the bottom of the cake pan, it will not compact easily like a cheesecake base, but will firm up considerably once baked, so focus more on even coverage and no gaps. Bake this at 350⁰ Fahrenheit for about 15-18 minutes, until dark golden and caramelized. Cool.
- To make the filling, it’s best to have all your ingredients weighed out separately and ready to go, except for the heavy cream, keep that cold. First, hydrate your gelatin with the cold water by stirring the water aggressively with a whisk while slowing streaming in the gelatin. Set to the side.
- Add your milk to a medium sized pot and set over medium/low heat. Put your egg yolks in a medium sized bowl and set that bowl on a damp towel. The damp towel will keep the bowl from moving around on you. Add your vanilla to the eggs, then once your milk is steaming, add the sugar and salt to the eggs and whisk vigorously for 2 minutes. It should lighten in color and leave “ribbons” once whisked long enough.
- Pour your hot milk into the egg yolk mix in 3 additions, whisking the eggs the entire time, then pour it all back into the pot and continue whisking over medium/low heat. Once the milk/egg mix reaches 180⁰ Fahrenheit, take it off the heat and pour it into the bowl that originally ball had the egg yolks and sugar. This will stop the cooking.
- Now add your gelatin and stir until it is smooth, then add the peanut butter and repeat. Set this to the side.
- Now I’ll whip my heavy cream by hand (soft peaks), and give the peanut butter mix a good stir every few minutes to disperse some of the heat and keep it smooth. The peanut butter mix can be warm, but not hot, when you add the whipped cream.
- If you did everything exactly as I told you, the mix should be an okay temperature to immediately fold in the cream, once you’ve beat it to soft peaks. Err on the side of less stiff, it should still flow around the bowl when held at an angle.
- Fold in the whipped cream in 3 additions. I honestly just use the whisk and stir it lightly, which also helps if you’ve over whipped your cream. Stir only until everything seems completely smooth and there are no lumps, then pour the mousse on top of the cooled base and put in the freezer for minimum 6 hours.
- If you’re worried about the Jelly layer, which has the most room for technical and equipment error, just do the ganache in the notes below, and you’ll have a stellar chocolate and peanut butter cake.
- Only start the Jelly layer once your mousse is completely frozen solid (tap it, it should be rock hard). Pour your grape juice into a medium pot and set over medium heat.
- Combine your sugar, Agar Agar, and salt and mix this well. Agar Agar must be well combined with sugar (just like pectin) before adding it to the liquid or it will clump up.
- While stirring the grape juice moderately quickly and continuously with a whisk, slowly sprinkle in the sugar/agar mix.
- We need to watch this like a hawk, stirring it frequently (not necessarily continuously, but it doesn’t hurt). We’re waiting for the juice to hit 212⁰ Fahrenheit (boiling). Once it hits either 212⁰ F or a full boil, let it continue to cook for an additional 60 seconds (No longer than 90 seconds), then immediately pour it into a separate container to start cooling down. The longer you cook Agar Agar, the firmer it will set, and there’s no going back once it is too far.
- Visual indicators do work, but you have to be positive of the difference between simmering and boiling, which is why I encourage you to use a thermometer of some sort. Here at elevation, 202⁰ F is a full boil, so I rely on both indicators and instruments.
- The agar agar will only start to set once it falls below 100⁰, and to keep our peanut butter and grape layers clean, I usually let the mix sit in the bowl on the counter for a good 30-45 minutes or go, stirring it every 5-10 minutes, so it doesn’t melt any of the peanut butter layer.
- I have the mousse cake basically in the fridge where I’m going to let it set, before I pour the Grape layer on. Since it is liquid, it can be difficult to move once you pour the grape layer, plus the movement will only eat away at the top of our mousse and kill our dreams of clean layers.
- Once you pour the grape layer, let it firm up in the fridge for 2 hours, or til set, then you can transfer it to the freezer to freeze completely before unmolding.
Special Instructions / notes:
Ganache Topping – Heavy Cream – 130g, Dark Chocolate – 110g, Butter – 30g. Heat your heavy cream til hot and pour it over the chocolate and butter. Let sit 2 minutes, then stir together til smooth, starting in the very center and slowly working your way out. Pour immediately onto cold PB layer, sprinkle with Maldon Salt before cooling, if you desire.
If you’re looking to “Elevate” your dessert game but don’t know where to start, I’d say the ganache version of this recipe is perfect for you. Nothing is super technical or difficult, and you end up with a visually pleasing dessert, that’s basically like eating a giant Reese’s.. who’s going to criticize that?!