ADD Simple Mills Organic Nut & Seed Flour All Purpose Baking Mix, psyllium husk powder, and salt into a food processor and pulse to aerate.
ADD the frozen and cubed butter and pulse until it looks like a corse meal.
POUR in ice water and pulse until combined.
REMOVE the dough from the food processor and press together to form a disk and wrap.
PLACE in the fridge for 1-2 hours, or overnight.
MAKE the filling:
POUR olive oil into a large pot and saute the onions and garlic over medium-low heat for 5-10 minutes, until translucent.
ADD carrots and chicken and cook until the chicken is no longer pink on the inside.
ADD arrowroot starch and cook over low heat, stirring constantly, for 5 minutes.
MIX in the milk, peas, salt, pepper, thyme, oregano, black pepper, salt, and butter.
DIVIDE the filling equally among 4-14 oz ovenproof ramekins or one 9x9 inch square baking dish and let cool while you roll out the dough.
PREHEAT the oven to 375º F
ROLL the dough into a 14x14 inch square and cut into four circular pieces about 1 inch larger than the ramekin.
TRANSFER the circles over the filled ramekins, using a spatula, and gently press the dough to encourage it to fold over the rim.
BRUSH with egg wash and cut 4 slits into the top using a knife.
BAKE for 45-50 minutes, or until the top is golden brown and the filling is bubbling hot.