Preheat the oven to medium-high heat, or 350°F.
In a medium-sized bowl, combine the large egg, Worcestershire sauce, fresh lemon juice, seafood seasoning Dijon mustard, and mayonnaise.
In a second medium-sized bowl, mix the lump crab meat, fresh parsley, and crumbled crackers.
Combine the wet ingredients with the crab meat mixture. One by one, drizzle wet ingredients into the crab meat mixture and lightly mix.
Use a paring knife to gently cut open a "pocket" in the top of each chicken breast. Mound up the crab meat stuffing in each slit, and fold the chicken over the mound to close the slit.
Mark the exteriors of your chicken breasts on a hot grill pan.
Put the stuffed breasts in a casserole dish rubbed with olive oil or sprayed with cooking spray.
Sprinkle flour mixed with spices or a dry herb seafood seasoning over the chicken and pour melted butter on top.
Put the chicken in the oven and bake for 20 to 25 minutes. Remove when the internal temperature reads 165°F and the chicken breasts are a golden brown.
Remove the chicken from the oven and serve it.