Pecorino Flans with Tomato Sauce (Pecorino Tortas con Salsa di Pomodoro)

Ingredients

• ¹⁄₄ cup olive oil
• 6 cloves garlic, minced
• 1 (28-oz.) can whole peeled tomatoes, crushed by hand
• Kosher salt and freshly ground black pepper, to taste
• 8 large basil leaves, roughly chopped
• Unsalted butter, for greasing
• 6 eggs
• 2 ¹⁄₄ cups heavy cream
• 1 ³⁄₄ cups grated Pecorino Romano
• Boiling water, for baking