Preheat oven to 375℉.
Place olive oil in a small pan over MEDIUM heat. Add onions and brown for 10-15 minutes, stirring frequently. Allow the onions to cool.
In a large bowl, combine beef, cooled onions, bread crumbs, jalapeños, cheese, salt, and pepper. Mix gently but thoroughly as to not overwork the meat.
Lay one square of pastry on a board or work surface. Use a third of the beef mixture to form a log down the center. Fold the pastry over the beef mixture on one side, then brush along the edge with egg mixture to create a “glue”. Continue to fold the roll over so it’s fully encased in pastry, and the edges line up on the egg glue line, then press the pastry lightly to ensure a good seal. Repeat steps with each pastry square.
Flip each beef roll so it’s seam side down, then cut into 6-8 pieces. Place the pieces onto a sheet pan and bake for 30-35 minutes or until the pastry is golden brown. You may need to rotate the tray during baking to ensure even browning.
Allow to cool slightly before serving.
Based on 90% lean ground beef
Nutrition information per serving: 250 Calories; 129 Calories from fat; 14.3 g Total Fat (6.4 g Saturated Fat; 2.7 g Monounsaturated Fat); 35.4 mg Cholesterol; 363.6 mg Sodium; 15.4 g Total Carbohydrate; 0.8 g Dietary Fiber; 13.4 g Protein; 2.04 mg Iron; 117.2 mg Potassium; 0.02 mg Thiamin; 0.09 mg Riboflavin; 3.1 mg Niacin (NE); 0.1 mg Vitamin B6; 0.9 mcg Vitamin B12; 2.4 mg Zinc; 9.2 mcg Selenium; 28.5 mg Choline.
This recipe is an excellent source of Protein, Niacin (NE), Vitamin B12 and Zinc. It is a good source of Iron.