Preheat oven to 425 degrees F. Toss prepared vegetables in a bowl with 2 Tablespoons olive oil, or enough to generously coat. Place on a rimmed baking sheet, making sure to not overcrowd the vegetables. Season with salt and pepper. Bake 15-30 minutes or until the vegetables are tender and start to brown. Remove from oven.
Cut 8 slices of bread. Brush one side with olive oil.
Spread Basil Pesto Aioli on the opposite side of four slices. Layer asparagus, bell peppers and Provolone cheese. Top with other slice of bread (olive oil side out).
Heat in a panini press until crust is golden brown and the cheese is melted. Serve immediately.