• Cilantro leaves, for garnish
Cut each avocado in half lengthwise and remove the pit. Carefully scoop the flesh from the shell and dice it. Toss the diced avocado with the tomato, onion, cilantro and lemon juice. Stir to mix, and season to taste with salt and pepper.
Season the salmon fillets with salt and pepper. In a medium sauté pan, heat oil until smoking over medium-high heat and cook salmon, fleshy sides down, for 4 to 5 minutes on each side or until cooked through. Transfer fillets to platter to cool slightly.
Spoon heaping tablespoons of avocado salsa onto each flour tortilla. Gently flake each salmon fillet with a fork. Top the tortillas with salmon, sour cream mixture (see below) and cilantro leaves. Serve immediately.
To make Chipotle Sour Cream: Stir together sour cream, chipotle pepper and adobo sauce; mix well. Season to taste with salt. Serve right away or refrigerate.