Whisk 2 cups milk and vinegar together in a bowl; let rest until milk sours, about 2 minutes.
Sift flour, white sugar, cocoa powder, baking powder, baking soda, and salt together in a large bowl; whisk to combine.
Whisk milk mixture, melted unsalted butter, eggs, red food coloring, and 2 teaspoons vanilla extract together in a bowl.
Pour milk mixture into flour mixture and stir until just combined; the batter should be lumpy.
Heat a cast-iron skillet over medium-low heat and spray with cooking spray. Drop batter by 1/4-cup onto the skillet and cook until bubbles form and the edges are dry, 3 to 4 minutes. Flip and cook until browned on the other side, 2 to 3 minutes. Repeat with remaining batter. Transfer cooked pancakes to a baking sheet and keep warm in the preheated oven.
Beat cream cheese and softened butter together in a bowl until light and fluffy, about 2 minutes. Add 1 cup confectioners' sugar, 1/4 milk, and 1/2 teaspoon vanilla extract; beat until smooth, adding more milk to reach desired consistency. Pour cream cheese glaze over pancakes and dust with remaining confectioners' sugar.
