In a large saute pan, saute onion in evoo over medium-high heat. Add bell pepper, celery, and garlic; season with salt and pepper. Cook, stirring frequently, until vegetables are softened, 5 to 7 minutes.

Add lentils and quinoa to saute pan. Cook, stirring and mixing until hot.

Stir in tomato paste, vinegar, date honey and chili powder and ½ cup water. Simmer until thickened, stirring occasionally, 6 to 8 minutes, add more water if needed to prevent sticking and burning.

Season the mixture with more salt and pepper, to taste. Spoon onto buns, and serve immediately with pickled vegetables or raw veggie sticks.