Preheat the oven to 375F. Line a large baking sheet with parchment paper

While you prepare the vegetables, place the bread slices in the oven for 10 minutes, flipping them over half way through, until they start to toast slightly (keep an eye on them so they don't burn). Remove them from the oven and set them aside to cool

Combine the cauliflower florets and the diced squash in a large bowl. Add the 2 tablespoons of melted coconut oil, dry thyme and salt and toss well, using your hands, until well coated. Transfer to the lined baking sheet and bake for 30 to 35 minutes, until fork tender, but not mushy

In the meantime, prepare the bechamel sauce. Melt the coconut oil in a small sauce pan over medium heat. Add the corn starch and cook for about a minute, stirring constantly. Slowly pour the canned coconut milk and non dairy milk, whisking constantly until well incorporated. Add the salt and pepper and cook for another minute until it thickens

Turn off the heat, add the cheese and whisk until its completely melted. Set aside

Break the bread into pieces and place it the food processor. Process until it turns into bread crumbs.

To prepare the topping,  place 1 cup of the bread crumbs (you can store rest in the freezer for future use) in a medium bowl. Add the nutritional yeast and salt and mix well

Coat a 9x6 inch baking dish with cooking spray. Spread about half of the bechamel sauce at the bottom. Place the roasted cauliflower and squash on top, and pour the rest of the sauce on top. Sprinkle the bread crumb topping evenly and drizzle the melted coconut oil over it. Bake at 375F for  20 to 25 minutes, until the top starts to brown. Serve warm