In a small bowl, dissolve the active dry yeast in the warm water. Let it sit for about 5 minutes, or until it becomes frothy.
In a large mixing bowl, whisk together the flour, sugar, and salt.
In another bowl, combine the milk, eggs, and melted butter. Add the yeast mixture to this bowl and mix well.
Gradually add the wet ingredients to the dry ingredients, stirring until the batter is smooth and free of lumps.
Cover the bowl with a clean kitchen towel and let it rise in a warm place for about 1 hour, or until the batter has doubled in size.
Heat a non-stick skillet or griddle over medium heat and brush with vegetable oil.
Pour a small amount of batter (about 2-3 tablespoons) onto the skillet for each blini, spreading it slightly to form a small round pancake. Cook until bubbles form on the surface and the edges look set, about 1-2 minutes.
Flip the blini and cook for another 1-2 minutes, or until golden brown and cooked through.
Transfer the cooked blini to a plate and cover with a kitchen towel to keep warm. Repeat with the remaining batter.
Enjoy your meal!