Cheesy chicken bacon broccoli & rice casserole

Cheesy Chicken, Bacon, Broccoli & Rice Cass.
adapted from: What's Cookin' Chicago (from ATK) 
(Printable Recipe)

4 c. cooked rice
3-4 chicken tenders, cooked and shredded
2 c. broccoli florets, steamed
4 slices bacon
1-2 Tbl. bacon grease
1/4 onion, finely chopped
3-4 Tbl. flour
1 (14 oz.) can low-sodium chicken broth
1/2 c. half-and-half
2 Tbl. Dijon mustard
1 1/2 c. Parmesan cheese, grated
1/2 c. Cheddar cheese, grated, opt.
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Cook bacon in a large skillet over medium heat until crisp.  Remove bacon and discard all but 1 or 2 Tablespoons of the grease.  Add chopped onion and saute a few minutes.  Gradually add flour and whisk until a thick paste forms.  Whisk in chicken broth, half-and-half and Dijon and stir until thickened.  Stir in cheese until melted.  Layer rice, shredded chicken and broccoli in a 8x8 casserole dish.  Pour cheese sauce over the top.  Crumble bacon and sprinkle over the top.  Bake at 350 degrees for 10-15 minutes or until heated through.