Whisk all crepe ingredients until smooth and lump-free.
Cook thin crepes in a lightly greased skillet until lightly golden on both sides. Set aside.
Heat butter and oil in a large pan. Cook ground beef until browned.
Add onion and garlic; sauté until softened.
Stir in peppers and cook until tender.
Add tomato paste, salt, pepper, paprika, and water. Simmer for several minutes.
For the béchamel sauce, melt butter in a saucepan and stir in flour.
Slowly add milk while whisking continuously until thickened.
Season with salt, pepper, and nutmeg.
Preheat oven to 200°C (400°F).
Grease a baking dish and place one crepe on the bottom.
Spread a thin layer of béchamel, then add beef filling.
Repeat layers until all ingredients are used.
Pour a little milk over the top and cover generously with grated cheese.
Bake until golden brown and bubbly.
Let rest for 10 minutes before slicing and serving.