Spread a thin layer of mustard on each schnitzel. Mix the paprika powder and flour together, then coat each schnitzel evenly with the mixture. Let the coated schnitzel rest for 2 minutes.
Heat the oil in a large pan over medium-high heat. Add the chopped bacon and onions, fry for 4 minutes until the bacon is crispy and onions are softened, then remove and set aside.
In the same pan with the remaining fat, fry the schnitzel over medium-high heat for 3-4 minutes per side until golden and the internal temperature reaches 63°C (145°F). If the internal temperature is not yet reached, reduce heat to medium and continue cooking for 1-2 minutes.
Return the bacon and onion mixture to the pan and heat for 1-2 minutes to warm through. Serve the schnitzel topped with the bacon and onion mixture.