Heat the oven to 375°F (190°C). Place a 13x18 inch sheet pan in the oven.
Make the cinnamon swirl: In a bowl, mix together the sugar, 4 tablespoons room temperature butter and cinnamon. Add 1 tablespoon of melted butter and mix until combined.
Make the pancake batter: In a bowl, combine the milk and lemon juice. Let them sit for 2 minutes. Add the eggs, sugar, 3 tablespoons melted butter, a pinch of salt and vanilla. Mix until combined. In a separate bowl, whisk the flour, baking powder and baking soda. Combine the flour with the wet ingredients and whisk until mostly combined, but still with a few lumps.
Pour ⅓ cup of pancake batter in the cinnamon butter. Mix until incorporated. Add to a piping or ziplock bag and cut a small tip.
Add the remaining 3 tablespoons butter to the preheated sheet pan and brush all over. Pour the pancake batter in the pan and pipe cinnamon swirls all over the batter.
Bake for 15 to 18 minutes. Slice into 9 to 12 pancakes.
Make the glaze: combine the sugar and milk together. Pour over the pancakes.
