Beef Roulade with Mushroom and Carrot Filling and Potato & Apple Gratin

For the beef roulades: Place the beef roulades on a countertop, pat dry and season with salt and pepper. Brush with the mustard and top with the bacon slices. Peel the carrot and cut into finger-long thin sticks. Peel the onions and dice. Rinse the mushrooms in a colander. Evenly distribute the onion, carrot strips and mushrooms over the beef and roll up the roulade. Tie with kitchen string or hold together with skewers. Heat the oil in a Dutch oven over medium-high heat.  Add the roulades and cook until browned on all sides.  Rinse the marjoram (reserving some for garnish), pat dry and add to the pan. Add the red wine and broth. Cover and simmer for 90 minutes, checking occasionally to prevent the roulades from touching.

For the gratin: Rinse and peel the potatoes and cut into thin slices. Rinse the apple, cut into quarters, remove the core and cut the apple into thin slices. Grease a shallow ovenproof dish with butter. Place the potatoes and apple slices in the dish in layers. In a bowl, whisk the whipping cream with the egg, salt and pepper. Pour over the potatoes. Bake in preheated oven at 200 degrees C (approximately 395 degrees F) (gas mark 3-4, fan: 180 degrees C (approximately 350 degrees F) ) for 45 minutes.