Preheat oven to 400 degrees and prepare a baking sheet with foil or use a nonstick baking sheet. Bring a medium pot of lightly salted water to boil. Thoroughly rinse produce and pat dry. Slice asparagus diagonally into 1" lengths. Slice radish into thin rounds, then half-moons. Trim and peel and cut carrot into ¼" slices on the bias. Stem and slice basil into thin strips. Stem, core, and slice red bell pepper into ½" strips. Thinly slice green onions on an angle, separating white and green parts.

Arrange asparagus, carrots, and red bell pepper pieces on the prepared baking sheet. Drizzle with 1 Tbsp. olive oil and season with a pinch of salt. Toss to coat evenly. Place in oven and roast until crisp tender, about 9-12 minutes. Remove from oven and set aside.

Add gemelli pasta to boiling water. Cook for 7-9 minutes, or until al dente (pasta should still have a hint of firmness.) Measure out and reserve ½ cup of pasta water for finishing sauce. Drain pasta, return to pot, and set aside.

Place a medium pan over medium heat. Add white parts of green onions and evaporated milk to pan and cook until slightly thickened, 2-3 minutes. Season with a pinch of salt and pepper.

Add roasted vegetables and cooked pasta to pan with sauce and toss to coat evenly. If sauce is too thick, add 1 Tbsp. of reserved pasta water at a time to thin it out. Add peas, radishes, Parmesan cheese (reserving some for garnish), and sliced basil (reserving a bit for garnish). Toss to combine. Season with a pinch of salt and pepper.

Spoon gemelli pasta and vegetables into a shallow bowl. Garnish with reserved green parts of green onions, Parmesan cheese, and sliced basil.