Line an 8x8-inch pan with foil. Spray with flour-based non-stick cooking spray.

Into a large saucepan over medium-high heat, add the brown sugar, butter, and evaporated milk. Bring to a boil for 10 minutes, or until the temperature reaches Soft Ball Stage (234-240°F) on a candy thermometer.

Remove from heat and add confectioners' sugar.

Using a hand mixer, beat on low speed for 5 minutes, until the confectioners' sugar is fully incorporated and the texture is smooth and creamy.

Stir in the pecans.

Pour the entire mixture into the prepared 8x8-inch pan, using a spatula or the back of a spoon to spread evenly.

Let cool completely then cut into 1-inch squares and serve.