Step 1 In a cast-iron skillet, render the bacon over a low and sweet fire. Remove and drain the bacon, leaving the fat in the pan.
Step 2 Season the trout with salt and pepper, and flour the trout lightly. Add the trout to the skillet and fry in the bacon fat until crisp and golden-brown, 3 to 4 minutes. When the fish is nearly cooked, add the butter to brown and squeeze the juice of the lemon into the skillet.
Step 3Remove the trout from the pan and spoon some of the brown butter over the fish. Serve the trout with the reserved slices of bacon.