1. Whisk flour, salt, and pepper together in a large bowl.

2. In a separate bowl, whisk together melted butter, eggs, milk, and heavy cream.

3. Gradually add the dry ingredients to the wet ingredients, whisking until smooth.

4. Let the batter rest for 30 minutes.

5. Heat a small non-stick pan over medium heat.

6. Pour a small amount of batter into the pan and tilt to evenly coat the bottom.

7. Cook for 1-2 minutes or until the edges start to curl.

8. Flip and cook for another minute.

9. Repeat with the remaining batter until you have around 6 crepes.

10. In a large skillet, heat oil over medium heat.

11. Add sliced mushrooms and cook until they release their liquid and start to brown, about 5 minutes.

12. Add the shrimp and cook until they're pink and heated through.

13. Season with salt, pepper, and chopped fresh dill.

14. To assemble the crepes, place a spoonful of the mushroom and shrimp mixture onto the center of each crepe.

15. Sprinkle grated cheese over the top.

16. Fold the crepe into a triangle and press the edges together to seal.

17. Place the crepes seam-side down in a baking dish and sprinkle grated cheese over the top.

18. Dot the top with unsalted butter.

19. Bake in a preheated oven at 425°F (220°C) for 10-12 minutes or until the cheese is melted and bubbly.