Using a hand mixer, beat together the eggs and sugar. When well mixed add the oil and beat well.
Sift together the cake meal, potato starch, and salt and add to the wet mixture. Mix well. Stir in the chocolate chips or nuts if using them.
Refrigerate the batter at least 1 hour, but up to 24 hours.
Preheat the oven to 350 degrees and line a large cookie sheet with parchment paper.
Divide the batter in half. With the first half, shape it into a log that's flat on top and place it on the prepared baking sheet. Using wet fingertips, make sure the log is about 2 inches tall and even throughout. Repeat with the second log.
Bake at 350 degrees for about 30 minutes. When lightly browned, remove from oven and slice the logs into cookies about 1" wide. Lay them flat on their sides and sprinkle with cinnamon-sugar mixture.
Return the cookies to the oven and let cook about 5-7 minutes, then take out, flip over and let cook until golden brown (another 5-10 minutes).
Remove from oven and let them cool.
This mandel bread recipe doubles very easily! Just prepared 2 large cookie sheets for baking instead of one and be sure to rotate your pans top to bottom when baking.