Bring a pan over medium-high heat. Once hot, add 1 tbsp olive oil, onions, and zucchini. Saute for 2 minutes, add another drizzle of olive oil, garlic, cumin, turmeric, bay leaf, cinnamon stick, mix well and cook for 1 minute. Note: If you're using a traditional tagine, downshift the heat to medium-low for this entire stew portion of the recipe and place an inexpensive diffuser between the tagine and the heat source to keep the ceramic from cracking.
Add the chopped tomatoes with liquids and stir, Add the water, 1 tsp salt, cauliflower florets and butternut squash cubes.
Let it simmer for 20 minutes at medium heat partially covered. Stir occasionally.
After 20 minutes, remove from the heat and stir in the golden or maple syrup. Remove the cinnamon and bay leaf.
Preheat the grill pan to high heat until piping hot. Add corn and grill, turning often, until charred all over, about 10 minutes.
As desired, spread vegan butter over corn and season with salt.
Serve grilled corn with Tagine.