Heat the bacon. Add a drop of olive oil to a pan and heat the bacon on medium heat until desired crispiness is achieved. Don’t walk away! This bacon heats fast so flip often so it doesn’t burn.
Butter one side of the bread and place face down in a grill pan on medium heat.
While bread is toasting in the pan, build your sandwich. Spread peanut butter on the inside of the slice of bread. Layer 4-5 slices of bacon on top. Top with the other slice of bread, buttering the outside, flipping, and cooking until golden brown.