Preheat oven to 425 degrees F. In a large saute pan, heat 2 tablespoons oil over medium high heat. Cook onion, red bell peppers and green bell peppers until beginning to soften, about 3-5 minutes. Increase heat and add hash browns, stirring to combine. Cook 3-5 minutes then stir in cubed corned beef, hot sauce (if using), and salt and pepper to taste. Set aside.
Working on a 9x11 piece of parchment paper, stretch or roll pizza dough into a large rectangle. Transfer to a baking sheet and bake for 6 minutes.
Remove pizza from oven and brush dough with 2 tablespoons olive oil. Top with 1 cup shredded cheddar cheese, 1/2 cup mozzarella cheese and the corned beef hash. Make 4 wells in the hash and break an egg into each well. Top the hash with remaining 1/2 cup cheddar cheese and 1/2 cup shredded mozzarella.
Bake pizza until crust is golden and eggs whites are set, about 10-12 minutes. Remove from oven and garnish with chopped scallions.