I'm not sure where I found this recipe. I halved the original recipe to make 5 cups, so doubling it to make 10 cups would work well. Use the oil and seasonings of your choice. I have not tried it with homegrown tomatoes yet, but it should work.
1/2 Tbs. olive oil
1/2 medium onion, chopped
2 tsp. Italian seasoning (I use Penzey's salt-free Tuscan Sunset)
1 (28 oz.) can crushed tomatoes (I like Muir Glen organic)
1/2 tsp. baking soda
1 cup chicken or turkey broth
3/4 cup (6 fluid oz.) low-fat evaporated milk
pepper to taste
In 4-qt. saucepan, heat oil over medium-high heat. Add onion and sauté until tender. Stir in Italian seasoning; cook until fragrant, about 30 seconds. Add tomatoes and cook a few minutes. Stir in baking soda. Add broth and bring to a simmer for 10 minutes.
Remove the pan from the heat and use a stick blender to puree until smooth. (You can also use a regular blender if no stick blender is available.) Stir in evaporated milk and heat to simmer. Add pepper and salt as desired.