Make the sauce first. Put the corn cobs with the cream into a saucepan, and reduce the cream over medium-low heat by one half.
In another saucepan, heat one ounce of butter and saute bell peppers, garlic, shallots, and fresh corn until translucent. Add tequila and (if you're comfortable with this, careful, and have taken safety precautions) flame it. (Otherwise, just bring it to a light boil for two minutes.)
Strain cream into other ingredients and simmer for 15 minutes. Add parsley, green onions, salt and pepper. Whisk remaining butter into sauce. Keep the sauce warm.
Rub Creole mustard and seasonings on catfish fillets and marinate for an hour.
Season the cornmeal with the salt and pepper. Dredge the catfish in the cornmeal. Don't worry that not as much will stick as usual
Heat the oil in a heavy skillet until grains of cornmeal sizzle in it. Fry the catfish, turning once, till golden brown. Allow the oil to recover heat between batches.