three ingredient tomato soup

My kids cheer when I tell them we're having homemade tomato soup and grilled cheese sandwiches for dinner...and it's the easiest dinner EVER especially because for the grilled cheese sandwiches I use our sandwich maker. (I'll be sending each of my kids to college with a sandwich maker!)  We loved this soup.  I think this will be my go-to tomato soup recipe.

three ingredient tomato soup (adapted from inspiredtaste.net)
2 tablespoons unsalted butter or vegan option (this is much less than what the original recipe calls for)
1 onion, cut into large wedges
2 (28 ounce) cans crushed tomatoes
3 cups vegetable stock
1/2 teaspoon- 1 teaspoon fine sea salt or more to taste

Melt butter over medium heat in a Dutch oven or large saucepan.
Add onion wedges, water, tomatoes and 1/2 teaspoon salt.  Bring to a simmer.  Cook, uncovered for about 40 minutes.  Stir occasionally.
Blend the soup (I used an immersion blender) then season to taste.