Preheat the oven to 325°F. Spray 2 (8-inch) round cake pans with gluten-free nonstick spray and line the bottoms with parchment paper.

In a medium bowl, whisk together the flour, xanthan gum, baking powder, and salt. Set aside.

Add the butter and caster sugar to the bowl of a stand mixer fitted with the paddle attachment. Beat the sugar and butter together until light and fluffy.

Add the eggs, one at a time, beating well after each addition. Scrape down the bowl as needed to make sure there isn’t any butter stuck to the bottom. Add the vanilla extract and milk and mix until completely incorporated.

Add the dry ingredients to the wet ingredients and beat until combined.

Divide the batter evenly into the prepared pans and smooth into an even layer. Bake for 22-26 minutes or until a cake tester comes out clean. Be careful not to overbake and dry out the cakes.

Cool the cakes in the pans for 20 minutes, then remove from the pans and cool completely on a wire rack.

When the cake is completely cooled, make the whipped cream by adding the heavy cream, powdered sugar, and vanilla to a large bowl. Use a hand mixer to beat until soft peaks form.

To assemble, place one cake layer on a cake stand or plate. Spread the strawberry jam in an even layer over the cake, leaving about half an inch from the edge. Then top with the whipped cream. Gently place the next cake layer on top of the cake and dust the top with some powdered sugar. Serve immediately.