3 garlic cloves, crushed
1/4 cup plus 2 tablespoons extra-virgin olive oil, plus more for drizzling
1/4 cup all-purpose flour, plus more for dusting
1 1/2 cups whole milk
1/4 cup freshly grated Parmigiano-Reggiano cheese
2 tablespoons fresh lemon juice
Cornmeal, for dusting
1 pound pizza dough
4 slices thick-cut bacon (5 ounces)
1/2 lb. Scallops, sliced crosswise 1/4 inch thick
1 cup baby arugula
Preheat the oven to 475°. In a medium saucepan, cook the garlic in 1/4 cup of the olive oil over moderately low heat until it starts to sizzle, about 3 minutes. Whisk in the 1/4 cup of flour until smooth and cook, whisking, until light golden, about 3 minutes. Slowly whisk in the milk and cook, whisking, until the béchamel is smooth and thickened, 2 to 3 minutes. Whisk in the cheese. Stir in 1 tablespoon of the lemon juice and season with salt and pepper. Transfer the béchamel to a small bowl. Discard the garlic.
Lightly dust a baking sheet with cornmeal. On a lightly floured work surface, using a lightly floured rolling pin, roll out the dough into a 12-inch round. Transfer to the prepared sheet. Brush the remaining 2 tablespoons of olive oil all over the dough and spread the béchamel evenly on top, leaving a 1-inch border around the edge. Bake on the bottom rack of the oven for about 18 minutes, until the dough is almost cooked through.
Meanwhile, in a nonstick medium skillet, cook the bacon over moderate heat, turning, until golden and crisp, 7 to 8 minutes. Transfer to paper towels to drain. Chop the bacon.
Top the pizza with the scallops and drizzle with olive oil. Bake for about 3 minutes, until the béchamel is golden and bubbling and the scallops are just opaque.
In a small bowl, toss the arugula with the remaining 1 tablespoon of lemon juice. Top the pizza with the bacon and arugula and serve hot.