Heat oven to 425°F. On large rimmed baking sheet, toss gnocchi with 1½ tablespoons oil and ½ teaspoon black pepper. Arrange in even layer. Break off sausage pieces and add to pan. Roast 10 minutes.
In medium bowl, toss green beans and garlic with remaining tablespoon oil, red pepper flakes, and ¼ teaspoon salt. Toss gnocchi and sausage on baking sheet, scatter green bean mixture on top, and roast until everything is golden brown and tender, 8 to 10 minutes more.
Scatter kale over pan and roast until wilted, 2 minutes. Toss with lemon zest. Serve over ricotta and sprinkle with Parmesan if desired.
