Cook bacon in a medium skillet over medium heat 6 to 8 minutes, stirring every 2 minutes, until edges are golden and fat is rendered. Bacon should be crisp but not burnt. Transfer bacon to a paper towel-lined plate using a slotted spoon, leaving the fat in the pan.
6 oz bacon
Toast bread cubes in the bacon fat in the skillet 5 to 7 minutes, tossing every minute, until all sides are golden brown. Remove croutons to a separate plate and wipe skillet clean.
3 cups day-old baguette
Bring a small saucepan of water to 180°F, just below simmering with tiny bubbles on the bottom. Crack each egg into a small bowl and gently slide into the water. Poach eggs for 3 minutes for runny yolks with set whites. Remove with a slotted spoon and drain on a clean towel.
4 large eggs
Whisk white wine vinegar and Dijon mustard in a small bowl until combined. Slowly drizzle in olive oil while whisking constantly until the dressing emulsifies and thickens. Add 1 tablespoon warm bacon fat and whisk to combine.
3 tbsp white wine vinegar, 1 tsp Dijon mustard, 0.25 cup olive oil
Toss frisée lettuce with half the vinaigrette in a large bowl to coat evenly. Divide the greens among 4 plates. Top each plate with croutons, bacon, sliced shallots, and one poached egg. Drizzle the remaining vinaigrette over the eggs and serve immediately.
6 cups frisée lettuce, 6 oz bacon, 2 medium shallots, 4 large eggs
