Step 1 Cook the potatoes in boiling salted water until tender, 5 minutes. Drain.
Step 2 Meanwhile, steam the trout until the fish turns opaque and the skin and bones are easy to remove, about 6 minutes. Pull the skin off from the head to the tail. Remove the center spine and break the meat into chunks. Place the meat in the bottom of a 2 1/2- to 3-quart saucepan. Add the potatoes.
Step 3Cook the bacon slices in a skillet over medium heat until crisp, 2 minutes. Drain on paper towels. Crumble and reserve.
Step 4Reheat the bacon drippings over low heat and cook the onion, green pepper and celery until just tender, but not browned, 10 minutes. Pour the vegetables over the potatoes and fish. Top with the scalded milk. Season to taste with salt, 2 pinches of cayenne and black pepper.
Step 5Heat the chowder on low heat just until heated through. Do not boil. Sprinkle the reserved bacon bits on top.