Prep the veggies beforehand, peel the avocado and remove the seed, then cut the avocado into thin slices. Peel and chop a single red onion in half, then chop the onion.
Cut the Roma tomato into slices, then cut the slices in half. Wash and spin lettuce to remove excess moisture, chop the lettuce.
Place veggies into serving bowls and place in the fridge to chill.
Place a skillet over med-high heat, when the skillet is hot cook the thick-cut bacon until it is crispy. Remove the bacon and place it on a plate lined with paper towels to absorb grease.
Set bacon aside. Pour off the bacon grease and wipe the skillet clean and place over med-high heat.
Brush two slices of artisan bread with olive oil and place them into the hot skillet, toast until the bread is golden brown, flip the bread over and toast.
Transfer toasted bread onto a plate and spread vegan mayo on top of each slice of toast. Add avocado, tomatoes, red onion, lettuce, and thick-cut bacon on top.