Skip to Content

Gravy Without Flour: Gluten-Free, Grain-Free, and Perfecto for Keto

As an Amazon Associate, I earn from qualifying purchases.

Preview: This gravy without flour is the perfect recipe for you if you follow a low-carb, Keto, or gluten-free diet. Pureed caramelized onions are the only thickener.

If you think cutting carbs is the end of your gravy train, then I have good news for you.

In my last post, I talked about eating mashed cauliflower and suggested using gravy to make it more appealing. Because of the carbs in traditional gravy, I avoid using flour, cornstarch, or arrowroot to thicken.

Gravy without flour using onions

I tried coconut flour, but the texture felt gritty on my tongue. Same with chickpea flour. Most gluten-free flours are actually quite high in carbs, so that wasn’t an option either.

Then it hit me…

I remembered my recipe for Roasted Rosemary Chicken with “Instant” Gravy. Baked onions are the only thickening agent in the gravy

It occurred to me that caramelized onions should work the same way, and sure enough, they make a delicious gravy.

How do onions make a sauce thicker?

When using onions to make a sauce thicker, cook them down to access the natural gelatin within. I’m no food scientist, but my experience bears this out. The caramelizing process will accomplish this in addition to giving the onions extra flavor as they brown. Unfortunately, this will take time.

caramelized onions in a black skillet

It can take up to an hour to caramelize your onions on top of the stove. The heat must be low so as not to burn the onions. In addition, they will need to be stirred occasionally.

An hour? Who has that time for that?

Two ideas for making caramelized onions at your convenience:

  1. Use a slow cooker. No stirring or babysitting required. On the other hand, the flavor doesn’t seem as concentrated because not as much liquid is lost in the slow-cooker process.
  2. Fortunately, the onions can be prepared ahead of time, then frozen. I nearly always have a few packages of frozen caramelized onions in the freezer for recipes like this one. Pick a time when you know you’re going to be in the kitchen for a while anyway.

Do mushrooms make everything better?

I think so. If you are a mushroom lover like I am, try browning about eight ounces of mushrooms in the same skillet you used for the onions. Add half of the mushrooms to the blender, or just leave them in pieces. Add them to your finished gravy for visual interest and added flavor.

onion gravy with optional mushrooms

Recipe Notes

The flavor of your gravy will depend at least 99% on the quality and richness of your broth.  If you use bouillon or canned stock, check the taste before adding salt. If you have juices left from a roast or baked chicken, use that.

No broth in the pantry?

Use the water you have used to deglaze the pan in which you caramelized the onions. All those browned bits will add flavor and color to your gravy.

Looking to add more flavor?

Depending on your tastes and dietary limitations, try adding a few drops of Worcestershire sauce, steak sauce, or Kitchen Bouquet. (Check labels. These will likely add sugar and grains.)

If you are strict about no extra sugar or grains, try adding herbs such as thyme or parsley, unflavored Greek yogurt, or sour cream.

Disclaimer:  If cooked onions affect you adversely, this probably isn’t the recipe for you.

More Grain-Free Recipes

Did you enjoy this recipe? If so, you can help others and me by leaving a 5-star 🤩 rating inside the recipe below. No comments are required.

Hope to see you again soon!

p.s. If you have any questions or suggestions, you can email me privately: paula at

Yield: 8 servings

Onion Gravy Without Flour Recipe

Onion Gravy Without Flour Recipe

A gluten-free, grain-free, sugar-free gravy packed full of veggies that's perfect for a Keto diet.

Prep Time 10 minutes
Cook Time 45 minutes
Total Time 55 minutes


  • 1 tablespoon olive oil
  • 2 medium onions, peeled and sliced thinly (8-10 ounces)
  • 1 1/2 cups water or broth (chicken, beef, or veggie (see notes)
  • 1-2 tablespoons butter
  • Salt and freshly ground pepper


  1. Pre-heat a medium to large size skillet over medium heat on stove. The heavier the skillet, the better. Add oil, then onions, stirring frequently, especially during the beginning and the end, until they caramelize and turn brown. This may take between 30-45 minutes and can be done ahead of time. The onions should have cooked down to approximately 1/2 cup. Place onions into a blender.
  2. Add water or broth of your choice to same skillet you used for onions. Boil until all brown bits have dissolved into the water or broth. Add water or broth to blender containing onions saving back about a fourth cup.
  3. Starting at a slow speed and progressing to high, blend until smooth. Open blender and clean sides with a spatula. Add butter for smoothness. Keep blending. Add more liquid if gravy is too thick for your tastes. If you decide to add herbs, sour cream, or yogurt, do it last and blend just until smooth.
  4. Add salt and pepper to taste. (Sorry I can't give you an exact measurement. It depends on the broth you are using. My husband requires lots of pepper so there's that, too.


*I prefer to use homemade broth or stock so I can know exactly what's in it.

*If adding sour cream and yogurt, start with a couple tablespoons.

Recommended Products

As an Amazon Associate, I earn from qualifying purchases. But don't worry. This doesn't change the price you pay.

Nutrition Information:



Serving Size:


Amount Per Serving: Calories: 98Total Fat: 7gSaturated Fat: 3gTrans Fat: 0gUnsaturated Fat: 4gCholesterol: 18mgSodium: 117mgCarbohydrates: 5gFiber: 1gSugar: 2gProtein: 4g

Did you make this recipe?

Please leave a comment on the blog or share a photo on Pinterest

microwave mashed cauliflower
The Best Microwave Mashed Cauliflower Recipe
← Read Last Post
Steakhouse Orange Yeast Rolls
Orange Sweet Rolls From Your Bread Machine
Read Next Post →
Skip to Recipe