Preheat your oven to 350ºF (180ºC) and adjust the rack to the lower middle position. Lightly grease a 9-inch (23cm) springform pan and line it with parchment paper.

In a large mixing bowl, combine the sugar, melted butter, oil, eggs, milk, yoghurt, and vanilla. Whisk until everything is well blended.

In another bowl, mix the gluten free flour blend, almond flour, baking powder, xanthan gum, and salt together.

Gradually add the dry ingredients to the wet mixture, whisking until you achieve a smooth batter without any lumps.

Set the batter aside while you prepare the almond frangipane. In a separate bowl, mix the sugar, melted butter, eggs, vanilla, and almond extract until smooth.

Stir in the almond flour and salt until the mixture is well combined.

Transfer the frangipane to a piping bag with the end snipped off or use a large round piping tip.

Pour the almond cake batter into the prepared springform pan and smooth the top.

Pipe the almond frangipane evenly over the cake batter. For even coverage, pipe in parallel lines, then cross-pipe in the opposite direction.

Sprinkle flaked almonds evenly over the top.

Bake in the preheated oven for about 60-70 minutes. If the almonds start to brown too quickly, cover the cake with aluminum foil, shiny side up, and continue baking.

To check for doneness, insert a toothpick into the center. It should come out with some frangipane but no raw cake batter. The top should be slightly rounded and firm.

Once baked, let the cake cool in the pan for about 15 minutes before transferring it to a wire rack to cool completely.

Before serving, dust the cake generously with powdered sugar. It can be enjoyed warm or at room temperature.

Store any leftovers in a closed container in a cool, dry place for 3-4 days.