Cheeseburger Wellingtons

Name: Cheeseburger Wellingtons
Prep time: 25 min
Cook time: 30 min
Total time: 55 min
Cuisine: American
Ingredients: 1lb / 500g Ground/Minced Beef, (take out of the fridge 30 mins or so before needed (must be 20% - see notes)); Salt & Black Pepper, (as needed); Vegetable Oil, (as needed); 2x sheets of Puff Pastry ((see notes)); 8 slices of American/Processed Cheese; 4 tbsp Caramelised Onion Chutney ((see notes)); 4 tbsp Burger Sauce, (or sauce of choice); 16 Pickles/Gherkins, (patted dry to remove excess moisture); 1 Egg, (beaten for egg wash); 2 tsp Sesame Seeds