Heat oil in a large nonstick skillet over medium-high heat. Add onion, bacon, sage, garlic, and oregano; saute 4 minutes. Add sugar, pepper, and diced tomatoes, and reduce heat to medium. Cook sauce 10 minutes, stirring occasionally.
Cook the gnocchi according to package directions, omitting salt. Divide the gnocchi evenly among 4 shallow bowls; top each with 3/4 cup sauce and 1 teaspoon cheese.