Preheat your oven to 190°C (375°F). Lightly grease the muffin tin or line with paper liners, and have all ingredients ready at room temperature.
In a large mixing bowl, sift together the flour and baking powder to ensure an airy rise, then set aside.
Grate the sharp cheddar cheese using a box grater until you have about 1 cup of cheese, then set aside.
In a separate bowl, whisk the eggs until just combined, then stir in the milk and melted butter until the mixture is smooth and slightly frothy.
Pour the wet mixture into the dry ingredients, gently folding with a spatula until just combined. Avoid overmixing to keep the muffins tender.
Gently fold in the grated cheese and any optional add-ins like herbs, cooked bacon, or smoked paprika, distributing evenly throughout the batter.
Spoon the batter into the prepared muffin cups, filling each about two-thirds full, which allows room for rising and creates a nice domed top.
Bake in the preheated oven for 20–25 minutes, or until the tops are golden-brown and a toothpick inserted into the center comes out clean.
Remove the muffins from the oven and let them cool in the tin for 5 minutes, then transfer to a cooling rack to cool slightly and develop a crisp top.
Serve the muffins warm, perhaps with a pat of butter or additional cheese, and enjoy their melty, cheesy goodness.
