Adjust the oven rack to the center of the oven and pre-heat oven to 350˚ F.

Line the 8×8 pan with parchment paper for easy removal and give it a quick spray with cooking spray.

Place pecans in a medium skillet over low heat until lightly toasted. Set aside.

To brown the butter, the butter in a large saucepan on medium high. Melt butter, stirring only occasionally. Once melted, begin stirring often. Butter will crackle and pop as it browns and it will start to foam slightly. Once sizzling sound stops, continue stirring often until golden brown bits begin to collect on the bottom of the pan. The butter will smell slightly nutty and aromatic.

Remove from heat, pour into the bowl of a stand mixer fitted with a paddle attachment and allow to cool slightly –  about 20 minutes

Whisk together the dry ingredients: flour, oats, salt and baking soda in a medium bowl. Set aside.

Add brown sugar and vanilla to the brown butter and mix for 1 minute on medium speed until well combined. Add the egg, whisk until fully incorporated.

Add chocolate, toffee bits and toasted pecans to the dry ingredients, reserving a few pieces of each for the tops of bars. Stir gently to incorporate the add-ins.

Transfer the dry ingredients to the wet ingredients and mix until just combined with a sturdy spatula. Be careful not to overmix.

Scrape the batter into the prepared pan. The batter will be thick so make sure to push the batter into all of the corners of the pan with a spatula. Smooth the top and add the extra bits of toffee, chocolate and pecans, pressing gently into the batter.

Bake for 23-25 minutes, depending on your oven. They are done when the edges are golden brown and a toothpick comes out clean. Do not over bake or the bars will be dry. Let cool in the pan for 15-20 minutes before removing them for the pan and cutting.

Serve warm.