Preheat oven to 350 degrees. Lightly grease a 10-by-5-by-3-inch loaf pan.
Heat oil over medium-high heat in a large deep-sided skillet and sauté onion, carrots and celery until soft, about 15 minutes. If vegetables begin to stick, add a little bit of water to the skillet. Stir in garlic, thyme, basil and parsley. Let cook a few more minutes. Crumble the tempeh into the skillet and add soy sauce and broth. Reduce heat to medium and cook for about 5 minutes, stirring frequently. Transfer the mixture to a large bowl.
Add warm brown rice and bread crumbs to the bowl and mix thoroughly with a large spoon. The more you mix it and mash it, the better it will hold together when you bake it. Season with salt and pepper to taste.
Transfer the mixture into the prepared loaf pan and pack it down very firmly using the back of a spoon. Cover the top of the loaf pan with foil. Bake for 45 minutes, covered, then remove foil, and bake for an additional 15 minutes. Remove from oven and let rest for 5 minutes before unmolding. Run a knife around the edges of the cooked loaf to loosen, then flip onto a serving plate to unmold. Slice and serve.
Chef’s note: Recipe can be halved to serve 3 to 4 people. If halving, bake in an 8-by-4-by-3-inch loaf pan for 30 minutes covered, then 15 more minutes uncovered.
For the gravy
In a medium saucepan, heat oil over medium-high heat and sauté onion until soft. Add nutritional yeast and flour, and stir for about 1 minute. Add water, soy sauce, thyme and garlic powder. Continue to cook, whisking continuously, until mixture is very thick. Transfer gravy to a blender and purée until smooth. Adjust seasonings, and add salt and pepper to taste.