01 - Preheat oven to 350°F (175°C) and line two large baking sheets with parchment paper.
02 - In a large bowl, use an electric mixer to cream together the softened butter, granulated sugar, and brown sugar until pale and fluffy.
03 - Add the peanut butter to the creamed mixture, then incorporate eggs one at a time, beating thoroughly after each addition. Stir in vanilla extract.
04 - In a separate bowl, whisk together old-fashioned oats, all-purpose flour, baking soda, and salt.
05 - Gradually add the dry mixture to the wet ingredients, mixing gently until just combined. Do not over-mix.
06 - Fold in the chocolate candies, semisweet chocolate chips, and crushed mini pretzels, if desired.
07 - Scoop rounded tablespoons of dough onto prepared baking sheets, spacing each approximately two inches apart.
08 - Bake for 10 to 12 minutes until the edges are golden and the centers appear soft.
09 - Allow cookies to cool on the baking sheets for 5 minutes, then transfer to a wire rack to cool completely.