Oh guys, I’m super happy to be able to share this canned roasted tomato sauce that’s safe for water-bath canning with you! I have been on the search for awhile for a recipe to safely water-bath can roasted tomato sauce, similar to our family’s favorite Roasted Tomato & Vegetable Sauce for Freezing, but I just have to say you’ve got to be careful when searching the internet! I found quite a few “recipes” that didn’t have any specific amounts listed (“fill a pan with tomatoes, throw in a good handful of ______,” etc.) and then gave instructions for water-bath canning with the addition of citric acid.
Recipes like this are not considered safe by the USDA – adding citric acid to a concoction that is full of low-acid ingredients (olive oil, onions, garlic, fresh herbs and sometimes peppers), does not make it shelf-stable with boiling-water canning, especially when they’re not even measured amounts (see this article for more information). I know that many people have canned this way for years, but in my opinion, it’s just food and never worth even a possibility of sickness. (note: there’s a little more flexibility with sauces canned using a pressure canner, but it’s still recommended that you use a tested recipe.)
Okay, off my soapbox, ha! After all that, are you wondering how I came up with this boiling water safe canned roasted sauce? Well, here’s the deal: I searched and searched and couldn’t find any recipe safe for canning, but I wondered why I couldn’t just take the tomato sauce recipe from the Ball Blue Book that I’ve canned many times and instead of boiling the tomatoes, roast them instead. All the measured ingredients would be the same, only the cooking method would change.
This sounded like the solution to my search, but to make sure I called the preservation hotline from our extension agency (Oregon State where I live) and asked them if they thought it would be okay. I told them I’d be sharing it with my blog readers and they okayed the new cooking method, just cautioning me to keep all the other low-acid ingredients the same and to be sure to include the addition of citric acid or lemon juice. Which I did. And guess what? It worked great and has that nice roasted flavor that our favorite freezer sauce has – this is the sauce I’d been looking for!
Besides a great flavor, one of the other reasons I like to roast tomatoes for sauces is because I can skip the boiling-water-peeling step since it’s easy to just pluck the darkened skins off after roasting. So even though it took 2 batches of roasting for this amount of sauce (I can only fit the three pans shown in my oven at one time), it still took less time and work.
So basically you’re skipping the peeling and initial cooking part and replacing that with pans of roasted ingredients. After your ingredients are roasted, though, you need to bring to a boil so it’s nice and hot for water-bath canning so you transfer everything into a large stockpot. Which makes it easy to roast more pans – the first batch can wait in the pot for the second batch to roast. When everything is roasted, I like to use my workhorse immersion blender to make a smooth sauce, but you can so it in batches with a blender, too – it’s just messier.
A note on seeds: we don’t mind seeds in the sauce and I do squeeze out quite a few when I’m prepping the tomatoes for roasting, but if you’d prefer a seedless sauce, you can strain the sauce as you transfer from the roasting pans to the stockpot or after you’ve whirred it up – it’s up to you.
Oh, and I should mention that I took the in-process photos above before I realized that I should add all the other ingredients to the roasting pans first and then place the tomatoes on top of them. This makes it easier to pluck the skins off without losing any of the spices or other ingredients. Just in case you are, like, “hey that’s not what’s in the picture.” Gotta keep you all on your toes.
- 23 lbs. tomatoes (a variety of paste, heirloom and cutting provides the best flavor & consistency)
- 3 c. chopped onions
- 6 med. cloves garlic, chopped**
- 2 TB. olive oil
- 2 TB. balsamic vinegar (optional, but adds amazing flavor)
- 2 TB. canning salt
- 1 TB. dried oregano***
- 1 TB. dried basil
- 2 tsp. black pepper
- 1 tsp. crushed red pepper flakes (optional, but we love it)
- Citric acid or bottled lemon juice
- Heat oven to 425 degrees. Halving all ingredients to work in two batches, divide olive oil, onions, garlic, and dry seasonings between 2 or 3 roasting pans (what you have that will fit in your oven).
- Wash tomatoes, remove cores and blossom ends, cut in half and squeeze gently to remove some of the seeds. Place tomatoes, cut side down, on top of ingredients in prepared pans.
- Roast for about 40 minutes, turning once, until most of the tomato skins are puffed and browned. Remove from oven and pluck skins off with tongs (it's okay not to get every bit).
- Scrape roasted vegetables into a large stockpot, set aside and repeat the prep and roasting with remaining half of ingredients (unless you are making just a half batch - then just proceed to next step).
- Using an immersion blender, whir roasted ingredients until smooth (alternately, you can scrape from the roasting pans into a blender in batches and then add to the stockpot). If you'd like to strain to remove seeds, now is the time for that, too, using a wire mesh sieve.
- Bring smooth sauce to a boil over med-high heat, lower heat and then simmer sauce until it reaches desired consistency, stirring often, about 45 minutes to 1 hour. You can adjust salt or dry seasonings to taste at this point if you wish.
- Prepare a water-bath canner, jars, and lids.
- Adding ¼ tsp. citric acid to pints (1/2 tsp. to quarts) OR 1 TB. lemon bottled juice to pints (2 TB. for quarts), ladle the hot tomato sauce into hot jars, one at a time with ½-inch headspace. Wipe rims, attach lids and place in canner rack.
- Process 35 minutes for pints and 40 minutes for quarts (if processing both pints and quarts together, use the longer processing time). Note: start the processing time after canner comes to a full boil and then adjust heat to keep a low boil for the timed amount.
- Remove from canner to a towel-lined surface and let cool 24 hours. Check seals, label & store for up to a year.
**The tomatoes aren't roasted long enough to fully roast whole garlic cloves, so you'll want to chop them.
***Do not replace dried herbs with fresh, though you can increase or decrease the amounts given and add any other dried herbs you'd like.
Note for those just learning to can: click here for a step-by-step tutorial on water-bath canning.