Step 1

Set up a grill for indirect heat by building the coals on one side only. If using a gas grill, heat one side only to medium-high heat.

Step 2

Place a saucepan over the direct heat side of the grill and add 2 tablespoons olive oil. Add the onions with a pinch of salt, then move to the indirect heat side of the grill and cook until the onions soften, 3 to 4 minutes. Add the garlic and ginger and cook for another 2 to 3 minutes. Stir in the tomatoes and coconut milk.

Step 3

Bring to a simmer and season with salt and pepper. Move to the indirect heat side of the grill and simmer for 30 minutes, stirring occasionally, until all the flavors come together. Puree until smooth in a blender or with an immersion blender.

Step 4

For the Parmesan crisps: Place a large cast-iron pan over the indirect heat side of the grill. Sprinkle 1/4 cup Parmesan in one quadrant of the pan, then continue to create 4 separate circles that are about 3 inches in diameter. Close the top of the grill (your grill should be at 350 degrees F) and bake until golden brown, 3 to 4 minutes. Serve the soup with the Parmesan crisps if using!