Beat until well mixed. Add the flour and salt and stir with a sturdy spatula or wooden spoon until all of the flour is incorporated. The mixture will be crumbly. Stir in the nonpareils. leaving 1-2 teaspoons for the top.
Transfer the dough to the prepared pan and pat it to an even layer. I like to use a flat bottom glass or a metal hamburger spatula to help pat and even out the dough. Sprinkle reserved nonpareils evenly over the top and press gently to help them stay in place.
See Café Tips above in the post for more detailed instructions and tips.
Recipe adapted from Land O Lakes.