Preheat the Oven: Preheat your oven to 180°C (350°F) and adjust the oven rack to the middle position. Line a muffin tin with 7 pretty muffin wrappers.
Mix the Wet Ingredients: In a bowl, beat the egg, milk, yoghurt, vanilla extract and lemon juice together.
Combine the Dry Ingredients: In a separate bowl, whisk together the gluten-free flour, baking powder, brown sugar and ground almonds. Add the cocoa powder and chocolate chips to the dry ingredients and whisk to combine.
Combine Wet and Dry Ingredients: Add the dry ingredients to the wet ingredients and mix until just combined. Be careful not to overmix, as this can result in dense muffins.
Spoon into Muffin Tin: Divide the batter evenly among the muffin cups. You can fill them about two-thirds full.
Bake the Muffins: Bake the muffins for about 20 minutes or until a skewer inserted into the centre comes out clean. Let them cool in the tin for a few minutes before transferring them to a wire rack to cool completely.