Peel potatoes.

In a large pot, boil potatoes in water to cover until soft, 30 to 35 minutes. Drain, turn into bowl and mash.

In nonstick skillet, saute onion and garlic in two teaspoons oil until translucent. Add to potatoes. Season to taste with salt. Mix until smooth . Set aside.

Combine margarine and egg in mixer bowl and beat at low speed until blended. Alternately add flour and mixture of water and vinegar, beating after each addition. Begin and end with flour.

Divide dough into 6 portions. Divide potato filling in sixths.

On well floured board, roll each dough portion out to 10-inch square. Arrange one portion filling in strip across bottom, leaving end and sides clear. Fold over from bottom once, then fold in sides and roll to top. Repeat with remaining dough and fillings.

Freeze rolls 20 minutes.

Remove from freezer and cut into 3-inch pieces. Place on baking sheets sprayed with nonstick cooking spray. Top each with a few sesame seeds.

Bake at 375° until browned, 45 to 50 minutes.