You probably have all three ingredients on hand right now.

Simply Recipes / Jessica Furniss

I consider myself a brownie connoisseur.

I even had all the ingredients on hand alreadyit really is that easy!

Side view of three brownies stacked on top of each other with a bite bitten from the brownie at the top

Simply Recipes / Jessica Furniss

In this recipe, boxed brownie mix is combined with two eggs and one can ofsweetened condensed milk.

The sweetened condensed milk creates a decadent texture thats like a mix betweenfreshly-made fudgeand a brownie.

Slicing the brownies outside of the baking dish also avoids damaging the dish with a knife.

Sliced brownies laying on parchment paper with a bite taken out of one

Simply Recipes / Jessica Furniss

Then, utilize the fridge!

After your brownies cool completely on the counter, refrigerate them for just 15 minutes.

I use my wooden cutting board, but a sturdy plastic cutting board will work as well.

Side view of two brownies stacked on top of each other on a plate

Simply Recipes / Jessica Furniss

Line an 8x8-inch baking dish with parchment paper and spray the parchment with nonstick cooking spray.

In a large mixing bowl, combine the brownie mix, sweetened condensed milk, and eggs.

Use a wooden spoon or sturdy spatula to mix all the ingredients until fully combined.

The batter is fully mixed when no dry spots of brownie mix remain.

Dont overmix this batterbrownies work best when theyre mixed by hand just until everything is fully combined.

Pour the batter into the prepared baking dish and spread it out evenly.

The batter will be thicker than traditional brownie batter.

Remove the brownies from the oven and let them cool completely in the pan.

Once theyre cool, pull the brownies out of the pan with the parchment paper.

Chill them in the refrigerator for 15 minutes if you want a firmer brownie.

Place on a sturdy cutting board and slice into them.

Store the brownies in an airtight container on the counter for up to 3 days for optimal freshness.

They will keep in the freezer for up to 3 months.

Thaw them on the counter until they come to room temperature.

Next, I drag a knife through the batter to create swirls.

The peanut butter swirls balance out some of the sweetness in the brownies and create a really pretty effect.