Heat 4 cups of whole milk in a large, heavy-bottomed saucepan over medium heat, stirring continuously until it reaches 195°F, just before boiling.

Combine 3/4 cup of all-purpose flour, 1/4 cup of granulated sugar, and a pinch of kosher salt in a bowl. Whisk until well blended.

Melt 4 tablespoons of salted butter in a small saucepan over medium heat without browning, then set aside.

Once the milk is at the right temperature, add the flour mixture to the melted butter and stir until a smooth paste forms. Gradually pour this into the hot milk, whisking continuously.

Bring the mixture to a gentle boil and reduce the heat to low. Cook for 5-7 minutes, stirring often, until thickened.

Remove from heat and serve in individual bowls, drizzled with melted butter and sprinkled with cinnamon sugar.