My kitchen was brimming with garden tomatoes right now, so yesterday, I used them to make this homemade slow cooker spaghetti sauce. Since the tomatoes are watery, I mixed them with canned, drained tomatoes. And to keep things easy, I didn’t bother peeling or seeding the tomatoes.
Tomato sauce is best when you give it time to simmer but making it on the stove means you have to sit and watch it. The slow cooker is a much better option.
This slow cooker spaghetti sauce recipe makes a lot of sauce, so make it on the weekend for a week of dinners or freeze some of it. Serve it over any pasta, or for fewer calories and carbs, use spaghetti squash. Enjoy!

Creamiest Slow Cooker Spaghetti Sauce Recipe
Ingredients
1 pound ground beef (minced beef) - lean
½ large yellow onion - diced
6 cloves garlic - minced or chopped
6 medium tomato
14 ounces tomato - diced and drained
1 tablespoon Italian herbs (oregano, rosemary, thyme, and sometimes basil and parsley) - crushed
2 teaspoons red pepper flakes
1 teaspoon dried oregano - crushed
2 tablespoons sugar (white sugar)
½ teaspoon salt
1 package spaghetti - cooked
1 cup Parmesan cheese - grated
Instructions
- Brown beef in a large deep saucepan, adding onion and garlic halfway through.
- Drain fat, if needed. Add fresh tomatoes and cook over medium-high heat until they soften and break down a little (about 5 minutes).
- Add diced tomatoes, spices, sugar and salt. Stir and let simmer for about 10 minutes.
- Remove from heat and let cool for a few minutes. Use a handheld immersion blender to blend the mixture into a sauce-like consistency (be careful not to splatter yourself!).
- Ladle the sauce into a 5-quart slow cooker and cook on a low setting for 4 to 6 hours. Serve over cooked spaghetti or spaghetti squash.