Preheat oven to 350 degrees F.
Cut each sheet of frozen puff pastry into 1-inch strips, 8 inches long. On a large cookie sheet, weave strips into a lattice large enough to cover each pot pie. Brush beaten egg onto each lattice square. Bake for 5 minutes, or until dough has risen and turned light golden brown. Set aside until ready to assemble pies. Leave oven on at 350 degrees F.
Season chicken with seasoned salt and pepper. Heat oil in a large skillet over medium-high heat. Add chicken and saute until cooked through. Remove from heat and cut into chunks. Alternatively, you may use precooked chicken.
In a large saucepan, melt butter and then slowly add flour, stirring until consistency of peanut butter, but not brown like a roux. Slowly add cream and keep stirring. Add chicken base, garlic, and onion and stir until thickened. Add peas, carrots, nutmeg, if using, and cut up chicken. Remove from heat. Fill 4 individual oven-proof bowls with chicken mixture and then top each with a pre-cooked lattice square. Bake for 5 minutes or until bubbly. Any remaining pie filling may be frozen.