Break the frisée into roughly bite-sized pieces and finely dice/mince the shallot. Remove the crusts from the bread, if using, and cut into small dice. Set a pan of water to boil to poach the eggs and put each egg in a small bowl.
Cut the bacon into slices and fry over a medium-high heat until gently crisp. Remove the bacon from the skillet, leaving the rendered fat in the skillet, and set it aside to drain any excess fat.
Add the shallot to the pan and cook over medium heat for a couple minutes until softened. Remove the shallot to a small bowl, along with around 1 tablespoon of the fat, leaving a little fat in the skillet. If you don't have enough fat (if the bacon was leaner), add a little olive oil.
Toast the bread in the remaining fat/oil until gently crisp on at least a couple sides.
Meanwhile, add the red wine vinegar and Dijon mustard to the warm bacon fat and shallots and stir gently to emulsify. You can either toss the frisée with the dressing then divide between plates, or drizzle the dressing over the finished salad.
Also meanwhile, poach the eggs by optionally adding the white vinegar to the boiling water (you can skip the vinegar but it can help the egg white to stay together). The water should be a simmer rather than roaring boil. You can poach the eggs as you prefer, but it can often help to start by cracking each egg into a separate small bowl rather than cracking directly into the pot. Then swirl the water to form a small whirlpool and add an egg to the middle of the swirl. Once it starts to set, add the other egg. Poach them to around 2-3 minutes until the whites are white but the yolks are still soft.
Divide the frisée between two plates, top with the bacon pieces and add the croutons (if using) and egg on top. Drizzle over the dressing if not already mixed with the frisée, and serve.