September 4, 2021

Oven Roasted Tomato Sauce

Jars of oven roasted tomato sauce and a tray of fresh garden tomatoes

Slow-roasted garden tomatoes are one of the reasons I started a garden at Hilltop in Ely. The first time I made them, I had Roma tomatoes from the St. Paul Farmers’ Market bushel.

I sliced them all and lined them up on a sheet pan. They were lined up so nice and uniform. I sprinkled them with kosher salt and dried thyme, cooked them in the oven for 3 1/2 hours, packed them in zip-top bags, and froze them in one-cup portions.

For the winter, I used them in risotto, stewed white beans, and soups. It wasn’t until the holidays when I was making roasted tomato basil soup, that it occurred to me to blend them into oven-roasted tomato sauce, and that was a game-changer.

The flavors are so concentrated and rich. I now do both types of tomatoes each year and plan for most of my summer crop here to be turned into sauce or little sun-dried wonders. There are so many ways you can use the roasted tomatoes—in a roasted tomato caprese, pile it on top of some warm brie, serve with crostini or alongside grilled meats. Last year I spent the holiday season doing soup drops for friends instead of cookie swaps. Roasted tomato basil soup was a welcome change from all the sweets!

I plant two varieties of tomatoes, Early Girls and cherry tomatoes. Sometimes I add Romas to the mix too. These types give me the most consistent crop for the cool short growing season in Ely. Any green tomatoes on the vines before we close the cabin top for the season get turned into green tomato salsa.

Once the plants have been picked clean, or I can’t stand the thought of making one more can of anything, I pull them out of the ground. This usually happens first. I lay the plants on the ground outside the “garden cage” for the bears or deer or red squirrels to finish them off.

Watch me make this roasted tomato sauce on The Jason Show!

Oven Roasted Garden Tomato Sauce

Oven Roasted Garden Tomato Sauce

Yield: 2-3 quarts or 4 pints
This oven roasted tomato sauce is so simple, but is delicious every time. It's perfect for pasta, pizza, stirring into soups and stews, really anything you can think of. Roasting the tomatoes brings out a rich flavor for all kinds of tasty Italian dishes. Plus, you can freeze the recipe to use it all fall and winter.


  • Approximately 12 medium size garden tomatoes - or 12 dozen cherry tomatoes
  • 1 Tbsp kosher salt
  • 1 Tbsp olive oil
  • Spices like basil, oregano, hot pepper flakes (optional)


    1. Preheat oven to 250 degrees F.
    2. Slice tomatoes in half and arrange cut side up on a baking sheet. Sprinkle with sea salt and drizzle with olive oil.
    3. Bake for 3 1/2 hours and check them to see how juicy they are. Sometimes I cook them to the point of “sun-dried” (5 1/2 hours) other times I cook them to the point of roasted and condensed (3 1/2 hours) and use them to make a roasted tomato sauce like we are doing here.
    4. Blend tomatoes in a blender with juices, any residual olive oil, and herbs if using.


  1. Leave an inch and a half head room in each jar and can or freeze.
  2. If canning: boil in a sealed mason jar for 12 minutes with at least one inch of water over the top of the jar. Take jar out of the boiling water and wait for top of jar to pop and seal for dry storage. Any jars that don't pop can be frozen.

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