Preheat the Z Grills smoker to 350℉.
Place the tomatoes, garlic, and fresh herbs in an oven-safe pot. Add a drizzle of olive oil and a generous pinch of salt to the top of the tomatoes, then place the pot on the smoker.
Once the garlic is soft and golden, use a hand mixer to puree your tomatoes into a soup.
Add the room temperature cream to your soup and allow your soup to simmer on the smoker. The whole cooking process takes about 2.5 hours.
While the sou rests, make the grilled cheese sandwiches. Butter the sourdough bread and place the bread buttered-side down on a flat cast iron griddle alongside the soup.
Top the bread with shredded cheddar cheese and allow the cheese to melt. When the cheese is melted, remove the bread from the grill and finalize the sandwiches.
Garnish the soup with a drizzle of pesto and freshly sliced avocado (optional).
Serve hot and enjoy!