In a large saucepan over medium heat, sauté onions in olive oil until soft and translucent. Add garlic, keeping it moving in the pot, so the garlic doesn’t stick or burn, for about 3 minutes.

Sprinkle cornstarch over onions and garlic, and stir until cornstarch covers everything, like a gluten-free roux. Cook for 2 – 3 minutes, stirring constantly.

Add mushrooms, rosemary, thyme, and 2 1/2 cups of veggie broth. Mix until well combined, and cook for another 2 – 4 minutes, or until mushrooms have softened a little. If you have a handheld immersion blender, blend gravy in the pot until smooth.

If using a regular blender, carefully pour the mushroom and broth mixture into the blender jar, and blend using the safety tips in the sidebar, and carefully return blended gravy to the pot for finishing.

Cook for 3 – 5 more minutes, adding non-dairy milk, salt and pepper to taste. If your gravy is too thick, thin with more veggie broth, adding in increments rather than all at once. If your gravy is too thin, mix another teaspoon of cornstarch with two teaspoons of cold broth or water (whisk or shake in a small jar with a lid until there are no lumps), then pour into the gravy. Stir and continue cooking for another 2 – 3 minutes to allow cornstarch to further thicken the gravy. If needed, repeat until your gravy is the thickness you prefer.