Preheat oven to 425°.
Season romanesco with salt and roast for 15 minutes.
Then toss and add the zucchini, peas and scallions, continue roasting for 10 minutes.
Meanwhile, heat 3 Tbsp. oil in a large heavy pot over medium-high. Add garlic, ½ tsp. red pepper flakes, stirring often, until garlic is fragrant. Add wine and cook until liquid is almost completely evaporated, about 2 minutes.
Cook the pasta until very al dente (a couple minutes from being done).
Add 1 ½ cups of the pastas’ water to the garlic.
Drain the pasta and transfer to a pot with garlic & the water. Reduce heat to medium and cook, tossing often, until pasta is al dente and liquid is slightly thickened, about 3 minutes.
Gradually add cheese, tossing until a sauce starts to form. Remove from heat; add butter and toss to combine.
Add salt and pepper to taste. Toss in the veggies and top with more cheese.