Prepare brown rice according to package directions. Peel and chop vegetables to be roasted.
Preheat oven to 400 degrees. To a large mixing bowl add chopped sweet potato, squashes, broccoli, garlic, olive oil, and seasonings. Mix to coat evenly then spread onto a sheet pan, making sure not to overcrowd the pan for proper roasting (use 2 sheet pans if necessary). Bake in the oven for 25-30 minutes until vegetables are slightly browned and tender.
While the vegetables are roasting make the dressing. Mix Tahini, lemon juice, maple syrup, salt and pepper in a jar. Add water if needed to thin dressing for desired consistency and adjust seasoning as necessary.
To assemble the bowl, add chopped lettuce, brown rice, roasted vegetables, and dressing. Toss to coat. Garnish with pumpkin seeds and raisins.