Can I use Grands biscuits for this?
Yes. Pillsbury Grands work great, just separate them and give them space. Since they are thicker, plan on the longer end of the bake time and check a center biscuit for doneness (no wet dough in the middle). If you want extra insurance, gently press each one a little flatter before baking.
How do I keep the biscuit bottoms from getting gummy?
A few things help a lot: make sure the filling is thickened (it should coat a spoon), assemble while it is very hot and steamy (not watery-thin), and do not pack biscuits edge-to-edge. If your filling looks a little loose after adding chicken and vegetables, simmer 1 to 2 minutes before you pour it into the dish.
Can I make this ahead?
You can make the filling up to 2 days ahead and refrigerate it. When ready to bake, warm the filling in the oven (or on the stove) until steamy-hot, then top with fresh biscuits and bake.
What vegetables work best?
Classic frozen mixed vegetables are perfect (usually a peas, carrots, corn, and green beans blend). If using broccoli or cauliflower, keep the pieces small and thaw and drain them first so they do not water down the sauce.
Potatoes can work too, but use frozen diced potatoes, canned diced potatoes, or par-cooked small cubes. Raw diced potatoes usually will not get tender in the bake time.
Can I make it without cream?
Yes. Use more chicken broth plus a splash of milk, or use evaporated milk. It will be a little lighter, still cozy.