Adjust oven rack to middle position and heat broiler. Arrange bread slices on baking sheet and drizzle first sides with 2 tablespoons oil; flip slices and drizzle with 2 more tablespoons oil. Broil the bread until deep golden brown, about 3 minutes per side. Set aside.

In a large bowl, use your finger to crush tomatoes until tomato pieces are no larger than ½ inch; set aside.

Heat remaining 3 tablespoons oil in a 12-inch skillet over medium heat until shimmering. Add onion and cook until softened, 3 to 5 minutes. Add garlic and cook until fragrant, about 30 seconds. Add tomato paste, oregano, salt, and pepper flakes, and cook, stirring occasionally, until rust-colored, about 2 minutes. Add basil leaves and cook until wilted, about 30 seconds. Stir in reserved crushed tomatoes and bring to a gentle simmer. Reduce heat to medium-low and continue to simmer, stirring occasionally, until slightly thickened, 5 to 10 minutes. The sauce should be thick enough that a spatula should leaves trail in the sauce that slowly fills in behind it, but the sauce should still move when the skillet is shaken.

Remove skillet from heat and let sit for 2 minutes to cool slightly. In a small bowl, crack 1 egg. Using a rubber spatula or large spoon, clear a 2-inch-diameter well in sauce. Immediately pour in the cracked egg. (The well will hold yolk in place but may not fully contain egg white; this is ok.) Repeat with remaining eggs, evenly spacing the remaining 7 eggs in total around the skillet (7 around perimeter and 1 in the center).

Season each egg lightly with salt and pepper. Bring to a simmer over medium heat, cover, and cook, reducing heat as needed to maintain gentle simmer, until yolks film over, 4 to 5 minutes. Continue to cook, covered, until whites are just set (if skillet is shaken lightly, each egg should jiggle), 1 to 2 minutes longer for slightly runny yolks or 3 to 4 minutes for soft-cooked yolks.

Off heat sprinkle with Parmesan and chopped basil and drizzle with extra oil. Serve immediately with toasted bread.