Preheat the oven to 450°F. Grease 4 silicone molds with butter and arrange them in a muffin pan.

In the top of a double boiler, melt the chocolate and butter. Transfer the melted chocolate to a large bowl. Add the erythritol sweetener and whisk well.

Add the egg, egg yolk, and vanilla and whisk until combined. Add the almond flour and sea salt and mix until combined well. Divide the batter between the muffin molds. Bake for 4 to 5 minutes, until the edges are set but the middle is still jiggly. Cool in the pan for 1 minute.

Using an oven mitt, carefully remove the molds from the pan.

Place an upside down plate over one mold and flip them over to invert the cake. Remove the muffin mold. Repeat for the remaining lava cakes. Top the cakes with ½ scoop of vanilla ice cream and some raspberries, if desired.

Serve immediately.