These Mixed Berry Crumble Muffins are a delightful treat, perfect for breakfast or a snack.
Preheat your oven to 350°F (175°C) and prepare a muffin tin by greasing it or lining it with paper liners.
Using paper liners makes cleanup easier and ensures the muffins release cleanly.
In a small bowl, combine the flour and brown sugar for the crumb topping. Cut in the cold butter until the mixture resembles coarse crumbs. Set aside.
Use a fork or pastry cutter to evenly incorporate the butter into the dry ingredients.
In a medium bowl, mix together the flour, granulated sugar, baking powder, baking soda, salt, and lemon zest.
Sifting the dry ingredients ensures a smoother batter.
In another bowl, whisk together the milk, melted butter, and egg until well combined.
Ensure the melted butter is not too hot to prevent cooking the egg.
Gradually add the wet ingredients to the dry ingredients, mixing until just combined. Do not overmix.
Overmixing can lead to dense muffins, so mix until you no longer see dry flour.
Toss the frozen mixed berries with a tablespoon of flour to coat them, then gently fold them into the batter.
Coating the berries in flour helps prevent them from sinking to the bottom of the muffins.
Spoon the batter evenly into the prepared muffin tin, filling each cup about three-quarters full.
Using an ice cream scoop can help portion the batter evenly.
Sprinkle the crumb topping evenly over the batter in each muffin cup.
Press the topping lightly into the batter to help it adhere.
Bake in the preheated oven for 25-30 minutes, or until a toothpick inserted into the center of a muffin comes out clean.
Rotate the muffin tin halfway through baking for even cooking.
Let the muffins cool in the tin for 2 minutes, then transfer them to a wire rack to cool completely or serve warm.
Serving the muffins warm enhances their flavor and texture.