Make the caramelized apple and onion mixture. Heat butter over low-medium heat in a frypan. When melted, add the onions & sugar and cook over medium heat, stirring often, until the onions start to turn golden brown, about 8-10 minutes.
2 Tbsp butter, 1 Tbsp granulated sugar, 1 onion
Add the apple, cider vinegar and salt and cook, stirring often, until the liquid is reduced and the apples and onions are soft and golden brown, about another 15-20 minutes. Set aside to cool slightly while you make the sausage roll mixture.
1 Granny Smith apple, 2 tsp apple cider vinegar, 1/4 tsp salt
Preheat oven to Combi Steam, 350°F/180°C, 30% (low) steam. Line a baking tray with parchment or silicone paper and set aside.
Make the sausage rolls. Put the ground pork, garlic powder, thyme, fennel seeds, salt, pepper, cayenne and breadcrumbs into a large bowl. Tip in the apple and onion mixture, and mix with your hands or a spoon until everything is very well combined. Divide the mix into eight even portions.
2 lb ground pork, 1 tsp garlic powder, 3 stalks thyme leaves, 1 tsp fennel seeds, 3/4 tsp salt, 3/4 cup panko breadcrumbs, 1/2 tsp ground black pepper, 1/4 tsp cayenne pepper
Place one puff pastry sheet on your countertop and cut it in half, so you have two rectangles. Take a portion of the filling mixture and spread it along one long edge of the puff pastry rectangle, like a very long sausage. Brush the other edge of the rectangle with egg wash, and carefully roll up the pastry sheet with the sausage filling, until the ends overlap and encase the filling. Place seam side down, and cut the roll evenly into 4 smaller sausage rolls. Place the sausage rolls on the baking tray, slightly apart.
4 sheets frozen puff pastry
Repeat with the remaining puff pastry sheet to make 32 sausage rolls in total.
Brush the tops of the sausage rolls with egg wash, and use a sharp knife to score a couple of slits into the top of each one, to allow the pastry to rise. Sprinkle the sausage rolls with sesame seeds.
1 egg, 3 Tbsp sesame seeds
Put the sausage rolls into the oven and cook until they are puffy and deep golden brown, about 25 minutes. Serve hot.