Cheesy Catfish Chowder

So catfish was on sale at Peapod again. While I typically make catfish sinegang or Bittman's "Catfish Poached with Ginger and Soy Sauce," it was time to branch out. To the internet! And behold - this recipe (via Allrecipes.com) came to light. Did I have everything? Close enough. A search through the fridge produced a few stalks of limp celery and a half-bag of forlorn, drying carrots; an IM sent across the hall revealed both a baking potato and a large container of cow juice that I could borrow. Thus came about my first attempt at a milk-based soup - the version below incorporates my modifications.

• 2 tbsp. butter
• 1 medium onion, diced (about 1 cup; more is fine)
  
• 1/2 cup diced celery
• 1 cup diced carrots
  
• 2 cups chicken stock
• 1 large baking potato, cut into 1/2-3/4 in. cubes
  
• 3 cups whole milk, divided
• 1/3 cup flour
• 1 tsp. celery salt
• 1 tsp. salt + more to taste (used maybe 1-1/4 tsp. total)
  
• 1/2 tsp. cayenne pepper
  
• 1/2 teaspoon ground black pepper + more to taste (used maybe 3/4 tsp. total)
  
• 1 bay leaf
  
• 1- 1/2 lbs. catfish fillets, cut into 1 inch pieces
• about 1 cup grated cheese (this time I used a mix of Parmesan and Parmigiano-Reggiano)
  

In a Dutch oven over medium heat, melt butter and saute onions, carrots and celery for a few minutes, stirring occasionally, till the vegetables soften a bit.

Add potatoes. Cook 10 or so minutes, so vegetables are soft but still firm.

In a small bowl, whisk the flour into 1-1/2 cups of milk. Add to Dutch oven and mix.

Add the rest of the milk, the salt, celery salt, pepper and cayenne pepper. Cook, stirring occasionally, until the mixture thickens - maybe 5-7 minutes. Taste and correct seasoning.

Add catfish. Cook another 5 or so minutes till fish flakes easily on a fork but isn't overdone.

Stir in cheese; cook another minute or so, then turn off heat. Serve with more grated cheese, if you like.

NOTE: This came out wonderfully - vegetables were cooked through but not mushy; the catfish was moist and soft and chewy. A bowl apiece is more than enough dinner for myself, John and Bradley; the rest is currently cooling on my counter.