In a medium bowl, combine the mashed potatoes, greek yogurt, egg, cheese, ham, chives, salt and pepper. Mix well and set in the fridge for 20 minutes to set up.

Place a sheet of parchment paper on a sheet pan and remove the mashed potato mixture from the fridge. Crush the crackers and place on a small plate. Using a small cookie scoop or two spoons, shape the mixture into tablespoon sized balls, roll each in the crumbs, then place on the sheet pan. Put the prepared croquettes in the fridge for at least 2 hours to left the balls set up.

After 2 hours, preheat the oven to 375°F. Melt the butter in the microwave or on the stovetop and stir in the paprika. Remove the balls from the fridge, drizzle with the paprika-butter mixture, then pop into the oven. Bake for 20-22 minutes until golden-brown, before the bottoms start to burn.

Remove from the oven, let cool slightly and serve with mustard dipping sauce.