01 - Preheat oven to 350°F. Line an 8x8-inch baking pan with parchment paper, ensuring an overhang for effortless removal.
02 - In a large mixing bowl, whisk together rolled oats, whole wheat flour, ground cinnamon, baking soda, and salt.
03 - In a separate bowl, thoroughly blend creamy peanut butter, honey, melted butter, egg, and vanilla extract until smooth.
04 - Pour wet mixture into dry ingredients. Mix gently until fully incorporated.
05 - Fold in raisins and chopped walnuts to distribute evenly.
06 - Transfer prepared mixture into lined baking pan and press firmly into a uniform layer.
07 - Bake for 22 to 25 minutes or until bars are golden at the edges and set in the center.
08 - Allow to cool fully in the pan. Lift out using parchment, then slice into 12 even bars.