In a medium bowl, mash the avocado, and stir in the prepared basil pesto and lime juice. Leave it as chunky or smooth as you prefer. Add a pinch of salt and a bit of black pepper.
Spread the avocado pesto on each slice of toasted bread, followed by a slice of cheese if you prefer. Layer your desired veggies and top with another slice of toast. Cut in half, and enjoy!
Try grilling your veggies if you like a softer cooked veggie. The avocado pesto is fantastic on a BLT sandwich too!