Polenta with Sausage and Bean Ragu

Polenta: Add water to chicken broth to make 4 cups; bring to a boil in a 2-qt saucepan. Sprinkle in cornmeal gradually, whisking to prevent lumps. Reduce heat to simmer; cook, stirring, 5 minutes until polenta is thick. Stir in Parmesan, cover and let stand. Ragu: Meanwhile, cook sausage in large nonstick skillet over medium-high heat 3 minutes, breaking up clumps until no longer pink; drain fat. Add onion and zucchini; sauté 3 minutes until zucchini is just tender. Stir in tomatoes and beans; cook, uncovered, 2 minutes until mixture is hot and sauce is slightly thickened.