Prepare the chicken breasts
Pat dry the chicken breasts. Using a sharp knife, cut the chicken breasts in half horizontally nearly all the way through. Open each breast wide. Place a piece of parchment paper on top of a cutting board, place each opened chicken breast on top of the paper, then cover the breast with another sheet of parchment paper and flatten the chicken breast with a meat mallet or rolling pin to a thickness of 1 cm / 1/2 inch. Remove the paper. Spread dijon mustard over each breast and season with salt and pepper.
Roll into a roulade
Place a slice of ham and two slices of cheese onto each chicken breast. Evenly and tightly roll the chicken. Place on plastic wrap. Wrap the chicken roulade in the plastic wrap tightly and use the excess plastic on the sides to twist. Tie the excess plastic. Repeat with the remaining chicken breast. Place in the fridge for about 30 minutes to chill.
Pour the vegetable oil into a heavy-bottomed pot. Make sure it covers about 5 cm / 2 inches of the pot. Place over medium heat and heat to 170°C / 325°F. Prepare three plates. Add flour, pinch of salt and pepper to one plate. Beat the eggs and heavy cream in a second plate and combine breadcrumbs, sesame seeds, paprika, turmeric and chia seeds (optionally) in a third plate. Dredge the chicken first in the flour mixture, then the egg mixture, and then in the breadcrumbs mixture. Make sure you get each layer of coating evenly. Transfer to a plate.
Fry and bake
Using a skimmer, gently place each chicken cordon bleu into hot oil (170°C / 325°F). Fry for about 7 - 8 minutes on each side or until the exterior is nice, golden brown and crunchy. Check the interior of the chicken breast. If the center of the meat is not 68°C / 160°F place the Chicken Cordon Bleu on a baking sheet and cook until the temperature is reached, for about 5 - 10 minutes at 175°C / 350°F. If the temperature was already reached when frying, then place the chicken cordon bleu on a plate covered with kitchen towels to drain the excess fat.