Homemade muffins and cupcakes are usually a far cry from professionally baked ones, coming out flatter and more compact. If you really care about that domed, picture-perfect top, though, Food52 offers a few tricks.
Consulting expert baker Zoe Nathan, the Food52 folks tested a few different approaches, from adding more flour (increasing from 1 1/4 cups to 1 2/3 cups), starting at a higher temperature, using the oven's convention setting, and leaving the original chocolate chunk muffins recipe as is.
The extra flour muffin was the only one that came out rounded. However, it also ended up tasting more flour-y and dryer, more like a purchased muffin than homemade. Despite the sinking of the muffin in the original recipe, however, staff preferred that version.
A floury muffin taste might not be worth the mounded look, but if you want to try it, Food52 suggests going with lighter and airier recipes (without heavy add-ins) and making the batter as light as possible by using a folding motion.
Check out their post for even more tips and details.
How to Make Domed Muffins | Food52