Put the flour in a small dry frying pan over medium heat and toast, stirring often, until it has darkened evenly to a light brown. Transfer the flour to a blender. Add the walnuts, liquid aminos, lemon juice,garlic, pepper, and half cup of the vegetable bouillon to the blender and blend until smooth. Add the remaining 1.5 cups of the bouillon and blend until smooth. Scrape the mixture into a medium saucepan. Bring to a simmer over low heat, and simmer, stirring often, until the mixture is thickened, about 2 minutes. Serve hot. This was developed especially for the zucchini boats, but is also good over brown rice, potatoes and vegetables.