Freshly grated black pepper
1/4 cup ham, chopped into 1/4 inch cubes
1/2 tsp. lemon juice
1 1/4 cups milk, heated until steamy, but not simmering
2 tbsp. flour
2 tbsp. unsalted butter
2 cups uncooked elbow macaroni
1 tbsp. salt
2 quarts water
1 tsp. cornstarch
1/2 pound cheddar cheese, grated