In a large pot of boiling salted water, cook pasta . Within the last 2 minutes of cooking time, add broccoli ; drain well.
Heat olive oil in a large pan over medium high heat. cook all the vegetables and keep them aside.
Melt butter in the same pan over medium heat. Whisk in flour until lightly browned, about 1 minute. Gradually whisk in vegetable stocks and milk, and cook, whisking constantly, until incorporated, about 1-2 minutes. Stir in heavy cream and garlic powder until slightly thickened, about 1-2 minutes.
Stir in Parmesan until well combined, about 1 minute. If the mixture is too thick, add more milk as needed.
Stir in pasta, broccoli and cooked veggies. Gently toss to combine; season with salt and pepper, to taste.
Serve immediately, garnished with coriander leaves, if desired.
