Heat a large nonstick skillet over medium-low or an electric griddle to about 350°F while mixing the batter.
Whisk flour, sugar, baking powder, baking soda and salt in a large bowl for about 20 seconds.
Whisk Greek yogurt and 3/4 cup milk until mostly smooth. Whisk in eggs, cooled melted butter and vanilla.
Pour wet ingredients into dry and fold just until no large flour pockets remain. Leave small lumps; do not beat smooth.
Rest 10 minutes. The batter should mound briefly, then slowly settle. If rigid, fold in milk 1 tablespoon at a time.
Lightly butter the griddle. Portion a level 1/4 cup batter and nudge into a 4-inch circle. Cook 2 to 3 minutes, until the edge is matte and center bubbles rise and begin to open.
Turn once with a thin wide spatula without pressing. Cook 1 to 2 minutes, until golden and the center springs back lightly with no wet batter line.
Adjust heat based on the first pancake. Butter lightly between batches and repeat, leaving at least 2 inches between portions.
