A delightful treat combining the richness of chocolate with the wholesome texture of oats.
Preheat your oven to 350°F (175°C) and grease a 9x13 baking pan.
Greasing the pan ensures easy removal of the bars after baking.
In a mixing bowl, cream together the granulated sugar, brown sugar, and 3/4 cup of butter until light and fluffy.
Softened butter mixes more easily and creates a smoother texture.
Add the egg to the creamed mixture and mix until well combined.
Crack the egg into a separate bowl first to avoid shell pieces.
In a separate bowl, combine the flour, baking soda, and oats. Gradually add this to the wet mixture, mixing until just combined.
Overmixing can make the bars tough, so mix until just incorporated.
Spread about three-quarters of the oat mixture evenly into the prepared baking pan.
Press the mixture firmly to create an even base.
In a saucepan over low heat, melt the sweetened condensed milk, chocolate chips, 1/4 cup of butter, and vanilla extract, stirring until smooth.
Stir constantly to prevent the chocolate from burning.
Pour the melted chocolate mixture over the oat base in the pan.
Spread the chocolate evenly for consistent flavor in every bite.
Drop spoonfuls of the remaining oat mixture over the chocolate layer.
Leaving gaps allows the chocolate to peek through for a decorative effect.
Bake in the preheated oven for 25 minutes, or until the top is golden brown.
Check for doneness by observing the color and firmness of the topping.
Allow the bars to cool completely in the pan before cutting into squares and serving.
Cooling completely ensures clean cuts and prevents crumbling.