Heat your oven to 350°F (175°C). Line your muffin pan with classic paper liners or tall parchment collars.
In a bowl, whisk together the rice flour, all-purpose flour, baking powder, and salt.
In another bowl, beat the softened butter and sugar until light and fluffy.
Add the eggs one at a time. Then mix in the vanilla and lemon zest.
Add the dry ingredients in two parts, alternating with the milk. Mix until smooth. Don’t overmix.
Spoon the batter into the muffin cups, filling each about three-quarters full.
Sprinkle a little sugar on top of each muffin.
Bake for 18–22 minutes, or until the tops are golden and the centers spring back when touched.
Cool for 5–10 minutes and serve warm or at room temperature.
