In a large mixing bowl, combine the instant yeast, sugar, hot water, and warmed milk. Stir until the yeast is dissolved and let it sit for about 5 minutes until frothy.

Next, add salt and oil to the mixture, then gradually incorporate the all-purpose flour, mixing until a soft dough forms. Knead the dough briefly on a floured surface, cover it with a kitchen towel, and let it rest for 15 minutes.

While the dough rests, preheat your oven to 375°F (190°C). Grease a pizza pan with a little oil to prevent sticking.

Once the dough has rested, roll or press it out into a 12-inch circle directly on the prepared pizza pan, ensuring an even thickness.

In a separate bowl, combine the all-purpose flour, brown sugar, granulated sugar, and cinnamon for the crumb topping. Add the softened butter and use your hands to mix until the mixture resembles coarse crumbs.

Spread the crumb topping evenly over the prepared dough, ensuring every inch is covered. Place the pizza pan in the preheated oven and bake for 15-20 minutes until lightly browned.

While the pizza is baking, whisk together the powdered sugar, vanilla extract, and milk to create the icing.

Once baked, remove the pizza from the oven and allow it to cool slightly for about 5 minutes. Drizzle the icing over the warm pizza in a zigzag pattern.