Preheat the oven to 350°F.

In a bowl, combine the sliced peaches, protein powder, cornstarch, lemon juice, cinnamon, and sweetener. Toss until the peaches are evenly coated.

Spread the peach mixture evenly in the bottom of a baking dish.

In a separate bowl, mix together the flour, protein powder, sweetener, baking powder, and salt.

Add the Greek yogurt, almond milk, egg, melted butter, and vanilla extract. Stir until a thick batter forms.

Dollop spoonfuls of the topping over the peach filling. It doesn’t need to cover completely — the topping will spread slightly as it bakes.

Bake for 25–30 minutes, or until the peach filling is bubbling and the topping is golden brown.

Remove from the oven and let cool for a few minutes before serving.