Rosemary-Honey Simple Syrup (Do this step first, at least one hour before you intend to bake the chicken.)
Bring water to boil in a small saucepan. Turn off heat. Add honey, stirring to dissolve. Add rosemary, and cover to steep for 1 to 2 hours. Remove any twiggy rosemary branches. Stir in optional Dijon mustard, until fully incorporated.
Preheat the oven to 350℉. Choose a large casserole dish (with a lid for GAPS).
Smashed Cauliflower
Wash cauliflower and remove outer green leaves. Place whole cauliflower (uncut) into a steamer basket over simmering water. Allow cauliflower to simmer or steam until very fork-tender, about 40 minutes. While cauliflower steams, prep and bake the chicken.When the cauliflower is very fork tender, carefully transfer it to a saucepan to cool slightly.
Break cauliflower into small chunks with a spoon. Transfer ⅓ to ½ of the cauliflower to a blender. Set aside until the chicken is done cooking.When the chicken is done cooking, use the pan juices: Measure out about ⅓ (to ½) the total pan juices, enough to puree the cauliflower to a creamy "baby food" consistency. Also add ½ teaspoon sea salt to the blender. Puree cauliflower till smooth, adding more pan juices as needed.Stir puree back into saucepan of small cauliflower chunks, smashing some of the cauliflower with the back of a fork. Place saucepan over lowest heat to heat gently.
Baked Chicken
Place chicken in large casserole dish. Spoon rosemary syrup over chicken. Drizzle olive oil over chicken. Season with salt and pepper, to taste. Cover for GAPS; otherwise, bake uncovered. Place in preheated oven for 45 minutes, until juices run clear when poked deeply with a knife. Remove chicken from the oven, and pour off pan juices needed for the cauliflower. Turn the oven heat down to 250℉.
Place Baked Chicken back into the warm 250℉ oven to keep it warm until you're ready to serve. Allow both chicken and cauliflower to get toasty hot, increasing heat and stirring the cauliflower, as needed. Serve with extra pan juices spooned over the top of both.
Notes
*For GAPS Introduction Diet, keep the chicken covered while it heats.