Rinse chicken and pat dry. Sprinkle lightly with salt and pepper.
Put 1 tablespoon oil in a 5- to 6-quart pan over medium-high heat. When hot, add 1/2 the chicken and brown on all sides, about 10 minutes total. As chicken is browned, transfer to a platter and add remaining chicken. Let cool to room temperature, about 10 minutes.
Add carrots, thyme, and remaining oil to frying pan. Stir often until carrots are slightly browned, about 10 minutes. Add flour and stir 1 minute longer. Add sautéed onions and garlic, white wine, broth, and port, and stir until boiling, about 5 minutes. Let cool to room temperature, about 40 minutes.
Put 1/2 the chicken in each of 2 foil pans (8 to 9 in. square). Spoon sauce evenly over chicken. Seal pans with foil, and freeze (see Cold Facts below).
Thaw 1 pan (see notes). Bake, covered, in a 375° oven until chicken is no longer pink at bone in thickest part (cut to test), about 1 1/2 hours (about 1 hour in a convection oven).
Cold Facts. Packaging: freezer bags and foil pans. Squeeze out all air and seal bag. For better protection of frozen foods during storage, seal each bag inside a second one. Lay bags flat in freezer until solid so they will stack. Seal foil pans with a double layer of foil to protect foods for storage. Label each dish with permanent marker. Make a master list of the dishes. As you remove each from the freezer, cross it off the list. For best quality, freeze meat mixtures no longer than six weeks, others three months.
Note: Nutritional analysis is per serving.