Beat eggs with sugar until slightly thickened and light in color, about 5-7 minutes. The mixture should almost double in size. (The eggs work as the leavening in this recipe, so don't skip this step). When finished beating, the mixture should form a ribbon when you lift the beaters out of the bowl.
Add the butter, vanilla, orange zest and orange extract; mix two more minutes. Stir in the flour until just combined. Add the cranberries and stir to mix thoroughly. The batter will be very thick and resemble cookie dough.
Spread batter in a buttered 9 x 13 pan. Bake for 40-50 minutes or until very lightly browned and a toothpick inserted near center comes out clean.