Brownie (noun)

1. A small, usually square piece of rich, chocolate cake, often with nuts or chocolate chips.
2. A small, chocolate-flavored square or bar that is typically made with flour, sugar, chocolate, and butter.

Origin:

From brown + -ie, first recorded in the late 19th century.

Examples:

1. She served warm brownies with ice cream.
2. He made a batch of homemade brownies.
3. The brownies were a hit at the bake sale.
4. She topped her brownie sundae with whipped cream.
5. The recipe called for melted chocolate in the brownies.