Sawing the Logs:
Beat egg yolks and one-half cup of sugar together, stir in cream cheese until smooth. Trim crusts from bread; use rolling pin to flatten each slice. Spread cheese mixture on a slice of bread. Top with another slice to make a sandwich. Do the same with the remaining slices.
Cut each sandwich lengthwise into 4 logs. Melt margarine. Mix cinnamon and remaining 1 cups sugar in a bowl. Dip each log into melted margarine, then in cinnamon sugar. Place on rimmed cookie sheets. Bake in a preheated 400 degree oven for 10 minutes. Makes 80 to 100 logs.
Note: to make ahead, freeze logs before baking on cookie sheets. Remove to freezer bags for storage. Take out as many as needed each time. Bake as before.