Line a jelly-roll pan with parchment paper that is cut to exactly fit bottom of pan.
In large bowl blend flour, pecans, baking powder and baking soda together.
Whisk 2 whole eggs and 1 egg yolk into a large mixing bowl Add sugar, zests and orange oil. Gradually whisk in melted butter; blending well. Add egg mixture to flour mixture until all is incorporated.
Empty dough out onto a gf floured surface; knead and mold into a stiff mass. (If dough is too soft, add more flour) Divide dough in half and roll each half into a 14" long log. Place each log onto the parchment paper lined pan, pressing top to flatten slightly.
Beat reserved egg white slightly and brush it on top of logs.
Bake for 30 minutes, until logs are light brown but give slightly when pressed.
Remove pan from oven and reduce temperature to 325 degrees F. Let logs cool for 15 minutes. Remove logs to a cutting board and cut into 1/2" slices on the diagonal.
Return bicottis to pan, laying them on their sides, and return to oven. Bake about 15 minutes. Remove biscottis from oven and set on wire racks until cold.
These wonderful Italian cookies can be stored in an airtight container for weeks.
We used The Gluten Free Pantry’s Country French Bread flour mix. To purchase this product please click the link below in our Recommended Tools section.