Add 1 tablespoon of oil to a large skillet, and saute the garlic and shallots for 2 to 3 minutes. Add the chopped parsley, Meyer lemon zest and shredded carrots, and continue to cook for another 3 to 5 minutes, until soft and fragrant. Add 1 tablespoon of the thyme last, and saute for an additional minute.
Allow the mixture to cool.
Mix the mashed potatoes with the Meyer lemon juice and minced turkey, and season with salt and pepper.
Blend the turkey mixture with the vegetable mixture, and to it, add the chicken stock and one beaten egg, in that order. The mixture should be firm enough to form into rounds. Add a little more stock if it's too dry.
Form the mixture into ovals about 1 1/2-inches long, and place on a lightly oiled baking sheet in the fridge for 1 or 2 hours.
When you're ready, beat the second egg lightly in a small bowl together with the milk and mustard.
Measure the breadcrumbs onto a plate, and season with salt and pepper, and the remaining 1/2 teaspoon of thyme.
Set the flour out on a third plate.
Heat 2 tablespoons of oil in a large skillet.
One at a time, take each croquette and first, dredge them in flour, then dip in the egg mixture, and then finally roll in the breadcrumbs to coat on all sides.
Place in the skillet, and repeat.
Brown them golden on each side, and then place on a lightly greased baking sheet.
Bake in the oven at 350°F for 15 to 20 minutes, or until golden browned on the outside, and thoroughly heated on the inside.
Serve drizzled with gravy if desired.