Preheat your oven to 350°F (175°C).
In a large bowl, combine the flour, sugar, baking powder, baking soda, and salt.
In another bowl, whisk together the buttermilk, melted butter, and eggs until well combined.
Pour the wet ingredients into the dry ingredients, mixing gently until just combined.
Fold in the rainbow sprinkles carefully using a spatula.
Grease a loaf pan and pour the batter into it, smoothing the top with a spatula.
Bake for 45-50 minutes, or until a toothpick inserted in the center comes out clean.
Remove from the oven and let it cool in the pan for 10 minutes before transferring to a wire rack.
Slice and serve warm or at room temperature, enjoying the festive flavors.
