Step 1

Preheat oven to 375 degrees F (190 degrees C).

Step 2

Bring a large pot of lightly salted water to a boil. Cook elbow macaroni in the boiling water, stirring occasionally until tender yet firm to the bite, 8 minutes. Drain.

Step 3

Whisk milk and flour together in a small bowl.

Step 4

Melt butter in a large heavy pot over medium heat. Pour in milk/flour mixture; stir constantly until thickened. Add most of the cheese, reserving a few tablespoons to sprinkle over top before baking. Mix in drained tomatoes, and salsa verde. Continue stirring until cheese is melted. Season to taste with black pepper. Stir in macaroni and thoroughly blend with the sauce.

Step 5

Divide among individual serving-sized ovenproof baking dishes or ramekins. Top with remaining cheese. and bake 10 minutes. Place under broiler for an additional 3-5 minutes, or until top is browned.

Step 6

Bake in preheated oven until hot and bubbly, about 10 minutes. Turn on the broiler and cook until tops are browned, about 2 to 3 minutes.