Preheat oven to 400°. Cut polenta into ¼ in slices; cut each slice in half. Brush with oil. Arrange in a single layer in shallow baking pan. Bake 15 minutes or until light brown, turning once.
Meanwhile, in a large skillet, cook sausage over medium heat for 5 minutes, turning to brown evenly. Remove from skillet, drain fat and wipe skillet.
Return sausage to skillet; add apple juice, vinegar and tomatoes. Bring to a boil; reduce heat and simmer, covered 8 to 10 minutes or until sausage is no longer pink.
To serve, divide salad greens among four plates. Arrange polenta slices and sausage pieces next to greens. Drizzle balsamic mixture over it all. Sprinkle with nuts.