Can I use frozen blueberries in this recipe?
Yes. Toss frozen blueberries (do not thaw) in 1 tbsp flour before folding into the batter to prevent sinking to the bottom. Bake time may increase by 2–3 minutes.
How much lemon zest should I add?
The recipe calls for zest from 1–2 lemons depending on preference. Start with 1 tsp zest, then add more if you want stronger citrus flavor.
Why did my muffins sink in the middle?
Overmixing the batter develops gluten and causes tunneling. Mix the dry ingredients separately, then fold the wet ingredients in gently until just combined.
Can I make these ahead?
Yes. Prepare the batter and refrigerate up to 24 hours, or bake and store muffins in an airtight container for up to 3 days at room temperature.
How do I know when they're done baking?
A toothpick inserted in the center should come out with a few moist crumbs, not wet batter. Tops should be golden and muffins should spring back slightly when pressed.