Roast your squash for about 20 minutes on 350 until soft, then slice in half and scoop out the seeds. Then place back into the oven for another 30 minutes or so.
Also add the tempeh to the oven to grill it - for the same amount of time (30 mins).
Meanwhile, fry up veggies with garlic and avocado oil for about 10-15 minutes. To make the cheese sauce, mix almond milk with nutritional yeast and mustard in a pan for about 5-10 minutes.
Scoop out the squash and top with cheese sauce, veggies, a piece of tempeh, and arugula on the side.