Preheat oven to 350degrees. Butter and flour and 9x13 pan. Melt butter and chocolate over low heat in a small saucepan. In a large bowl, whisk together eggs, sugar, salt and vanilla. Add melted butter and chocolate and stir until mixed. Gradually add flour and stir until just combined.
Pour 1/2 of batter into pan and then top with crushed cookies, followed by remaining batter.
Bake for 40-45min and cool completely before icing.
Speculoos Buttercream1/2 cup unsalted butter, softened
2/3 cup Speculoos Spread
1 teaspoon pure vanilla extract
1 1/2 cups icing sugar
2-4 Tbsp milk (start with 2 and add more if needed)
4 Speculoos cookies, crushed
Cream together butter, vanilla and speculoos spread with electric mixer. Gradually add icing sugar and milk and mix on low speed until incorporated. Beat at a higher speed until light and fluffy. Spread on cooled brownies and top with crushed speculoos cookies. Enjoy!