1. Preheat oven to 350 degrees; line baking sheet with foil.
2. Sprinkle chicken breasts with salt and pepper.
3. Mix dijon mustard and mayonnaise in a bowl; coat chicken with dijon mayo mixture.
4. Mix thyme and crushed pretzels in a sealable bag.
5. Roll chicken breasts in crushed pretzels and place on baking sheet.
6. Bake in a 350 degree oven for 20-25 minutes or until chicken juices run clear.