Preheat the oven to 200°C (400°F)

Add the white rice flour, tapioca flour, corn starch, brown rice flour, xanthan gum, baking powder, salt, brown sugar, and white sugar in a bowl. Whisk the ingredients and combine them. Then add the raspberries and mix them with the dry ingredients using a spatula.

Add the vegetable oil, eggs, lemon zest, lemon juice, buttermilk, and vanilla extract in a separate bowl. Whisk the ingredients together. Then add the dry ingredients and gently mix them using a spatula. Try not to overmix the batter.

Align a muffin tin or a cupcake tin with muffin liners and add a tablespoon of muffin batter. Then, add a teaspoon of raspberry jam to the center of the muffin. Then fill the liner to the top with the raspberry muffin batter.

Bake the gluten-free raspberry muffins for 17-19 minutes or until a toothpick inserted at the center comes out clean.

Allow the muffins to cool in the tin for 5 minutes before transferring them to a cooling rack.