Soak cashews in boiling water for 15 minutes. Drain and blend with extra firm tofu, lemon juice, and zest until smooth to create the tofu spread.

Thinly slice red onions and combine in a bowl with olive oil, vinegar, sumac, and a pinch of salt. Toss with chopped parsley and marinate for 10-15 minutes.

Wash and slice heirloom tomatoes, then combine with olive oil, minced garlic, parsley, basil, and lemon juice. Gently mix in tomatoes and let marinate for 5-10 minutes.

Spread creamy tofu spread on one slice of bread, layer with avocado slices, marinated tomatoes, and sumac onions. Top with lettuce and another slice of bread.