Cream Tarragon Chicken

I used to make a dish like this a long time ago.  It was the only fancy thing that I made way back then.  I thought of it a couple weeks ago and went in search of a recipe.  I found several (of course) but none exactly right.  So I made my own.

4 T butter
3 lbs boneless chicken thighs
3/4 t salt
1/2 t ground pepper
1 c chopped onion
1 c sliced fresh mushrooms
3 T flour
1 c dry white wine
1 t dried tarragon (or 3 t chopped fresh tarragon)
1 c heavy cream
1 c half and half

Melt butter over moderate heat.  Season the chicken with salt and pepper and add to the pan.

Cook the chicken until brown, about five minutes.  Turn and cook until just done, about five minutes longer.  Remove chicken from skillet and place in baking dish.

Reduce heat.  Stir in onion and cook until starting to soften.  Add mushrooms and cook until done.

Sprinkle flour over the onion/mushroom mixture and stir to combine.

Increase heat to medium.  Whisk in the wine and the tarragon and cook until the sauce starts to thicken.

Stir in the cream, half and half and any accumulated chicken juices.

Pour sauce over chicken.

Keep warm in 250 degree oven until ready to serve.  Cover baking dish with foil if it will be in the oven long.