St Patricks Rainbow Cookie Bars (Printable)

Buttery bars with white chocolate and sprinkles crafted for a colorful St Patricks occasion.

# Ingredient List:

→ Dry Ingredients

01 - 2 cups all-purpose flour
02 - 1/2 teaspoon baking powder
03 - 1/4 teaspoon salt

→ Wet Ingredients

04 - 3/4 cup unsalted butter, melted and cooled
05 - 1 cup granulated sugar
06 - 1/2 cup light brown sugar, packed
07 - 2 large eggs
08 - 2 teaspoons pure vanilla extract

→ Mix-Ins

09 - 3/4 cup white chocolate chips
10 - 1/2 cup rainbow sprinkles, divided

# Directions:

01 - Preheat oven to 350°F. Line a 9x9-inch baking pan with parchment paper, leaving overhang for easy removal.
02 - In a medium bowl, whisk together flour, baking powder, and salt. Set aside.
03 - In a large bowl, whisk melted butter, granulated sugar, and brown sugar until smooth. Add eggs and vanilla extract; whisk until fully combined.
04 - Gradually fold the dry ingredients into the wet ingredients with a spatula, mixing until just combined.
05 - Stir in the white chocolate chips and 1/3 cup of the rainbow sprinkles.
06 - Spread the batter evenly into the prepared pan. Sprinkle the remaining sprinkles over the top.
07 - Bake for 25 to 28 minutes, or until the edges are golden and a toothpick inserted into the center comes out mostly clean.
08 - Cool completely in the pan on a wire rack before slicing into bars.

# Expert Advice:

01 -
  • They come together in under an hour and require nothing fancy—just a whisk, a bowl, and confidence.
  • The contrast of soft, buttery cake with bursts of crispy sprinkles and melted white chocolate chips is genuinely addictive.
  • One batch makes enough to share, which always feels generous and far easier than it actually is.
02 -
  • Don't skip cooling completely in the pan—I learned this the hard way when I tried to cut warm bars and ended up with a crumbly mess that I had to eat with a spoon.
  • The sprinkles soften when they bake, which is actually the secret to why these taste so good—the sugar coating dissolves slightly and creates little flavor bursts instead of hard candy pieces.
03 -
  • Room temperature eggs mix in more smoothly and create a silkier batter, which directly translates to a better texture in the finished bars.
  • Don't fill your baking pan with parchment paper that goes all the way to the edges—let it hang over by about an inch on two sides so you have something to grip when lifting the whole batch out at once.
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