Swordfish With Mushrooms Gluten Free

How to cook perfect swordfish not well done. Cook it as I show with a little pink and it won't be dry.
It is the opposite of Chilean sea bass that can take over cooking and still be acceptable.

1&1/2 inch thick piece,
1/4 c. shallots,
1/4 c. yam flour,
regular flour if you want gluten,
1 T. ea. butter and olive oil, salt and pepper,
2 T. capers,
3 garlic cloves,
5 small button mushrooms,
1 tsp. lemon juice