Generously butter a muffin tin. Preheat the oven to 375℉.
In a large bowl, whisk together the 2 ½ cups gluten free flour , 3 teaspoons baking powder, 1 teaspoon ground cinnamon, ½ teaspoon fine sea salt, and ½ cup brown sugar. Lightly whisk the 1 large egg separately, then stir in the beaten egg, 1 cup plain yogurt, and ¼ cup unsalted butter. Gently fold in the 1 cup peaches.
Spoon the batter evenly into the muffin tin (fill each cup about two-thirds full). and let the batter rest for up to 20 minutes. Bake the muffins for 15-20 minutes, until a tester comes out clean.
Place the muffin tin on a wire rack to cool for about 10 minutes, then gently turn out the muffins onto the rack to cool completely.
Notes
Fresh or frozen peaches. I prefer to use fresh peaches here, but you can use frozen if needed. Thaw them a little bit first so that you can chop them up before adding them to the batter.
Grease the pan well. Generously grease the muffin tin to help the muffins release easily. You can also use liners if you prefer.
Rest the batter. Always let gluten-free batter rest before baking - the amount of time it takes to preheat the oven usually is enough - to hydrate the gluten-free flour. You will taste the difference!
Fill the muffin cups about ⅔ full for this recipe. I’ve found that about ⅔ full per cup is the sweet spot for the batter so that the muffins rise nicely but don’t overflow the pan.
Make them dairy-free. To make these muffins dairy-free, use melted coconut oil or non-dairy butter, plus a non-dairy yogurt.
Refined sugar-free. Add honey to the batter instead of the sugar for a lovely, floral sweetness that's a wonderful complement to the peaches. Or, try coconut sugar or maple syrup.