After baking, this pizza is topped with an abundance of colorful tomatoes -- it's practically a salad!
Preheat oven to 500 degrees, with racks in upper and lower thirds. Combine ricotta and Parmesan, season with salt and pepper, and stir in egg. On a baking sheet, drizzle pizza dough with 2 tablespoons oil and stretch or roll into a 16-inch-long oval. Spread ricotta mixture on dough, leaving a 1-inch border.
On a rimmed baking sheet, toss cherry tomatoes with remaining 2 tablespoons oil and season with salt and pepper. Bake cherry tomatoes on bottom rack and pizza on top rack until tomatoes are soft and skins have burst, 15 minutes. Remove tomatoes and bake pizza until crust is deep golden brown, about 8 minutes more. Toss cherry tomatoes with sliced tomatoes and season with salt and pepper. Transfer pizza to a cutting board and top with tomato mixture and oregano.
Heirloom Love Tomato plants that have been grown the same way for decades produce heirloom fruit. The vibrant varieties can be yellow, pale pink, purplish brown, even striped, and no two taste alike.