6ouncesbittersweet chocolate, chopped or use chips
1 ½cupgranulated sugar
¼teaspoonsalt
4large eggs
1teaspoonvanilla extract
1 ½cupsall-purpose flour
For the frosting:
1cupunsalted butter
4cupspowdered sugar, sifted
2teaspoonsvanilla extract
Pinchsalt
2-3tablespoonsmilk
Food coloring, as desired
Sprinkles, as desired
Instructions
To make brownies:
To make the brownies, preheat oven to 350°F. Grease a 9x13-inch baking dish or line with parchment paper.
In a saucepan set over low heat, melt the chocolate and butter. Stir until smooth. Remove from heat and add sugar and salt. Add the eggs one at a time, mixing after each. Stir in the vanilla extract. Add the flour and stir until just combined.
Pour batter into the prepared baking dish and bake until edges are set and the middles appear dry, about 20-25 minutes. Let cool completely.
To make frosting:
In the bowl of a stand mixer fitted with a paddle attachment, or in a bowl with a hand mixer, beat together the butter, powdered sugar, vanilla extract, salt and 2 tablespoons of milk on low speed until smooth.
Increase speed and beat until frosting is light, fluffy and creamy, pausing to scrape down the bowl if needed. Add more milk if needed to get the right spreadable consistency.
Color as desired with food coloring (I used green).
To cut and decorate into Christmas trees:
Cut cooled brownies into 4 long rectangles parallel with the short edges. Taking one rectangle at a time, cut from one corner diagonally across to the other edge 1 inch in. Then cut diagonally again back to the other side another 1 inch in. Use a ruler if you have one to make sure all cuts are even.
Repeat until you've cut 7 triangles, then repeat with the remaining brownie strips until you have 28 total triangles. You'll have a few scraps leftover from each side, which make great snacks!
Use a piping bag and tip, or a spatula, to top brownie triangles with the frosting. Add sprinkles as you like.
Store brownies in an airtight container at room temperature for up to 1 week, or well-wrapped with plastic wrap for a month or more. Be careful to let the frosting set up an develop a "crust" before storing, especially if you plan to stack brownies on top of each other.