Preheat oven to 425 degrees F.
Combine sausage, 1 egg, 1 TBSP of the dry ranch dressing mix, bread crumbs and shredded Jack cheese in a medium sized bowl. Mix to combine. Divide in half, then divide each half into thirds so that you have 6 mounds of sausage mixture.
Lay out the puff pastry into the 2 individual sections. Unwrap and cut along the seams so that you have 3 long sections per piece, or 6 total. (Hint: use a pizza cutter to cut dough into sections quickly!)
Place 1 mound of sausage onto each rectangle of puff pastry and shape using your fingers so that the sausage runs down the middle, in a long segment. Repeat for the remaining 5 sections of puff pastry.
Fold the puff pastry up the sides of the sausage so that the sausage is completely encased in the pastry. Pinch the seams to close.
Using a pizza cutter, divide each line in half, then into thirds so that each section yields 6 sausage rolls, 36 total. Pierce each roll with a knife to vent.
Place 18 on a cookie sheet sprayed with non-stick spray. Whisk 1 additional egg in a small bowl then brush each pastry with a little egg.
Bake for 18-20 minutes at 425 degrees F. Remove from oven and let cool.
Mix remaining dry ranch dressing mix with 1 cup of sour cream to use for dipping.