Preheat the oven to 425. Lay parchment paper on a sheet pan. Chop asparagus, purple onion, red pepper, and tomatoes. Lay on the sheet pan and toss with 2 T olive oil, italian seasoning, red pepper flakes, and salt and pepper. Roast for 15-20 minutes.
Boil water and cook pasta until al dente. Reserve pasta water for later use.
Chop garlic, juice lemon, shred the parmesan and chop the parsley.
When the veggies are done roasting, prepare the sauce. Melt butter in a large pan and add garlic and 2 T olive oil. Sauté a couple minutes until fragrant. Stir in the frozen peas and lemon juice and cook for a couple more minutes.
Stir in the roasted veggies, parmesan, parsley, pasta and pasta water. Season with additional red pepper flakes, salt and pepper, and italian seasoning if desired. Garnish with parmesan and parsley. Enjoy!