Freeze in an airtight container instead of zip-top plastic bags because frozen phyllo can be fragile. Serve with bottled chutney.
Place potatoes in a saucepan; cover with water. Bring to a boil. Reduce heat, and simmer 15 minutes or until tender; drain. Return potatoes to pan. Add sour cream, garlic and herb seasoning, salt, and pepper; mash mixture with a fork or potato masher until smooth. Stir in onions. Cool to room temperature.
Place 1 phyllo sheet on a large cutting board or work surface (cover remaining dough to keep from drying); layer with 2 additional phyllo sheets. Cut phyllo stack in half crosswise. Top each half with about 2 tablespoons potato mixture, leaving a 1/2-inch border. Roll up jelly-roll fashion, starting with short side. Tuck ends under; place rolls, seam sides down, on a baking sheet coated with cooking spray. Repeat with remaining phyllo and potato mixture to total 12 knishes. Lightly coat knish tops with cooking spray. Place knishes in an airtight container; freeze up to 3 months.
Preheat oven to 400°.
Place frozen knishes on a baking sheet coated with cooking spray. Bake at 400° for 25 minutes or until browned and crisp. Serve immediately.
Made these with my boyfriend and we had so much fun making them. Roll up eggroll fashion. Can't wait to do again and play with the mash potatoes seasoning.