Flourless Vanilla Bean Torte with Brown Butter

Preheat oven to 325 F.
Line the base and sides of an 8 inch round cake tin with baking paper and set aside.
In a large bowl, place the butter, natural sweetener, vanilla seeds and mix for 8-10 minutes or until pale and well combined. Scrap down the sides of the bowl.
Add the egg yolks into the butter mixture, continuing to beat until fully combined.
Add the almond flour and mix until smooth, then fold ricotta in (and lemon zest if desired).
In a separate clean (dry) bowl, beat the egg whites until stiff peaks form.
Gently fold the egg whites into the cake mixture. Pour the mixture into the prepared cake tin, smooth the top.
Bake for 40-45 minutes or until a toothpick inserted into the middle comes out clean.
Allow to cool completely in the cake tin.
While cooling, make the brown butter glaze.
Place the butter in a saucepan and heat on high for about 5 minutes. The butter will start to sizzle and fluff up. Watch for brown flecks (not black!) and remove from heat. Once the butter is brown, whisk vigorously while adding the sweetener. Add the vanilla seeds. Cool slightly so it thickens a little (or it will leak off of cake). Having a very cold cake will also help the brown butter to harden faster for a nice frosting.
Drizzle over cooled cake. Slice and serve.