Creamy Chicken And Mushroom Potpie

Preheat oven to 350F.
Trim the stems on all the mushrooms. Keep half (12oz) whole (unless large, then chop in half) and slice the rest. Set the sliced mushrooms aside.
Cube the carrots and onions. Smash the garlic cloves. Place the carrots, onions and garlic along the whole mushrooms on a baking sheet and sprinkle with olive oil, salt, pepper, and some fresh thyme. Roast in the oven for 8 minutes, then remove. Pour into crockpot. Place the defrosted chicken thighs on the baking sheet and salt and pepper them generously. Roast for 8 minutes. Remove and layer over the veggies in the crockpot. Throw in 4 additional thyme sprigs, flour, bay leaves and 2/3c of water. Season again with salt. Cover the crockpot and place on high for 4 hours.
2 hours before serving remove the puff pastry from the freezer and defrost, placing back in the refrigerator once fully defrosted. 30 minutes before serving, preheat the oven to 375F. Unfold the pastry onto a floured wooden/bread board, flour both sides, and cut 4.5" circles (as many as are being served). Place on a baking sheet lined with parchment paper and bake 10-15 minutes (until golden brown and dry to the touch).
10 minutes before serving, throw the green beans, peas, sliced mushrooms and cream into the crockpot. Stir and break up the chicken into smaller pieces. Recover and heat through an additional 10 minutes. Taste and season with salt as needed. Spoon into bowls and serve topped with the pastry rounds and a sprinkle of fresh thyme.