Creamy chicken and mushroom potpie

This is in the crock pot right now and smells divine!!

Combine in crockpot:
-8 ounces mushrooms, stems trimmed and halved if large
-4 carrots, cut into 1" pieces
-1 medium onion, chopped
-1/3 c all-purpose flour
-1/2 cup water
-2 sprigs fresh thyme (or about 1/2 tsp dried powder)
-1 bay leaf

Place on top:
1 1/2 lbs boneless, skinless chicken breasts (or thighs)
salt and pepper

Cover and cook on low for 7 - 8 hours or high for 4 - 5 hours.

Thirty minutes before serving, heat oven to 425. Using a 4 1/2" cutter or large glass, cut into 4 circles, place on baking sheet and cook for 8 - 10 minutes:
-1 sheet puff pastry (half a 17.3 ounce package), thawed.

Ten minutes before serving, add to crockpot and stir to combine:
- 1 cup frozen peas
- 1 cup frozen green beans or corn
- 1/3 cup heavy cream
- 1/2 tsp salt

To serve, place chicken mixture in bowls and top with pastry rounds.