Preheat the oven to 350ºF. Quarter the onion and tomatoes and cut the top off the garlic bulb. Arrange everything on a large sheet pan lined with parchment paper.

Drizzle olive oil generously over the veggies, especially the garlic bulb—this helps it roast to perfection. Then sprinkle the vegetables with Italian seasoning, salt, and pepper.

Place the sheet pan into a 350°F oven and roast for about 40 minutes, stirring halfway through to ensure the veggies cook evenly.

Once finished cooking, transfer the roasted vegetables to a large pot. Add the broth, and bring to a gentle simmer. Cover and let it simmer for 15 minutes.

Transfer the soup to a countertop blender and blend until smooth. Alternatively, you can use an immersion blender for ease.

Ladle the soup into bowls, pair it with a toasty grilled cheese, and savour every bite!