Heat the oil in a large skillet over medium-high heat with a bit of onion. When it begins to gently sizzle, add the remaining onion and cook, stirring often, for about 5 minutes or until it begins to soften.
Add the mushrooms, ginger root, celery, garlic, salt, black pepper, smoked paprika, Sage and Rosemary Blend, and thyme. Cook, stirring often, until the mushrooms release their liquid and begin to turn golden brown.
Reduce the heat and slowly stir in the vegetable broth and coconut aminos. Scrape the bottom of the pan with a wooden spoon to release any bits of vegetables or mushrooms. Simmer, partially covered, for 5 to 10 minutes; stir occasionally.
Spoon about 1/4 cup of the gravy into a small bowl and let it cool down for a couple of minutes. Add the arrowroot powder and whisk until smooth, then slowly pour back into the skillet while stirring. Simmer, stirring, until thickened.