In a mixing bowl, combine instant yeast, sugar, hot water, and warm milk until yeast dissolves, about 3 minutes. Mix in salt and oil, then stir in flour until a soft dough forms.

Lightly flour your work surface and knead the dough until smooth, about 1-2 minutes. Return to the mixing bowl, cover with a towel, and rest for 15 minutes.

Grease a 12-inch baking pan, transfer rested dough onto it, and press out evenly into a 12-inch circle.

In a small bowl, mix together flour, brown sugar, granulated sugar, cinnamon, and softened butter until resembling coarse crumbs, about 2-3 minutes.

Sprinkle crumb topping evenly over dough, preheat oven to 375°F, and bake for 15-20 minutes until edges are light brown.

While baking, whisk powdered sugar, vanilla extract, and milk in a bowl to reach desired icing consistency.

Once out of the oven, cool for a few minutes and drizzle icing over the warm pizza. Cut into slices and serve.