Nutrition per serving may change if servings are adjusted.
1 cup rolled oats
1 1/2 cups all-purpose flour
1/2 cup packed light brown sugar
1 teaspoon baking powder
1/2 teaspoon baking soda
1/4 teaspoon salt
1 large egg
1 large egg white
1/4 cup pure maple syrup
1 1/2 teaspoons pure maple extract
2/3 cup chopped pitted dates
1/2 cup walnuts, finely chopped, divided
Preheat oven to 325 °F. Line baking sheets with parchment paper or coat with cooking spray and set aside.
Spread oats on another baking sheet and toast them in the oven, stirring often, until light brown, 12 to 15 minutes. Transfer 13 cup of the toasted oats to a food processor or blender and grind them to a fine powder.
Combine whole and powdered oats, flour, brown sugar, baking powder, baking soda and salt. Whisk together egg, egg white, maple syrup and extract, and add to the dry ingredients; mix until almost smooth. Stir in dates and 14 cup walnuts.
Working on a floured surface, shape dough into 2 logs, each about 14 inches long and 1 1/2 inches thick. Sprinkle the logs with the remaining walnuts, pressing them lightly into the dough. Place the logs on a prepared baking sheet and bake until firm to the touch, 20 to 25 minutes. Transfer the logs to a rack to cool. Reduce the oven temperature to 300 °F.
Cut the logs diagonally into 1/2-inch-thick slices. Stand the slices upright on the baking sheet and bake for 40 minutes. Let cool before storing.