Cook pasta according to package directions, adding kale for the last 30 seconds of cooking; drain. Return pasta mixture to pan; cover and keep warm.
Meanwhile, for sauce, in a large skillet combine wine, 2 tablespoons green onion, and garlic. Bring to boiling; reduce heat. Simmer, uncovered, about 5 minutes or until liquid is nearly evaporated. Stir in evaporated milk. Bring to boiling; reduce heat. Simmer, uncovered, for 6 minutes. Whisk in pumpkin and sage.
Add sauce and 1/4 cup of the cheese to pasta mixture; toss gently to coat. Divide pasta mixture among warm shallow serving bowls. Top with the remaining 1/4 cup cheese and, if desired, additional green onions.