Sift dry ingredients into a large bowl.: The flour and baking powder will smell neutral but will feel light and airy after sifting, which helps create a tender texture. I sift to remove lumps and to evenly distribute the leavening, ensuring consistent rise. You should feel a faint powdery texture when you mix, and visually the mixture will look uniform. A common mistake is skipping sifting with dense flour, which can leave clumps that do not hydrate properly; if that happens, whisk vigorously until smooth.
In another bowl, beat egg until light. Add 1 cup milk and melted butter to bowl. Stir.: After whisking, the egg should look slightly frothy and paler, which signals aeration that contributes to lift. Add 1 cup milk and melted butter to bowl. Stir.: You will hear a soft whisking sound and see the glossy liquid come together, with the butter forming tiny ribbons before fully integrating. This emulsion helps distribute fat evenly for a silky batter. If the butter is too hot, it can cook the egg; let it cool if it looks steamy. A frequent misstep is adding very warm butter which leads to curdled wet mix; cool it to lukewarm before combining.
Add wet ingredients to dry ingredients and mix until moistened. At this point if it is too thick add the remaining 1/4 cup of milk to the batter a little at a time until you reach the consistency you want. Gently fold in blueberries.: At this point if it is too thick add the remaining 1/4 cup of milk to the batter a little at a time until you reach the consistency you want. Gently fold in blueberries.
Heat skillet or griddle over medium-low heat. Melt about 1/2 tablespoon butter on the surface. Ladle the batter (about 1/4 cup batter) into the skillet making 3-4 pancakes. Cook pancakes until bubbles form on top. Flip and brown the other side.: Melt about 1/2 tablespoon butter on the surface. Ladle the batter (about 1/4 cup batter) into the skillet making 3 to 4 pancakes. Cook pancakes until bubbles form on top. Flip and brown the other side.
Wipe out any excess butter with paper towels. Repeat with remaining batter.: Repeat with remaining batter.