Bring a large pot of heavily salted water to a rolling boil on your stovetop, drop in the elbow macaroni, and cook according to package directions until it reaches a perfectly tender, slightly soft bite. Strain the hot macaroni into a large colander, shaking it firmly to remove all heavy pooled water, then immediately transfer the warm noodles into a very large mixing bowl.

Sprinkle the three-quarters cup of granulated white sugar and the apple cider vinegar straight over the hot, steaming macaroni, and use a large rubber spatula to toss the noodles continuously for 60 seconds. Rushing this step while the pasta is hot is crucial because the expanded starches instantly absorb the sharp acid and sugar deep into the core of the noodles, ensuring your salad tastes highly seasoned from within rather than muted and bland.

Spread the dressed macaroni out slightly in the bowl and let it sit undisturbed on the counter for 15 to 20 minutes until it cools completely to room temperature and has fully absorbed the vinegar-sugar liquid base. While the pasta cools, finely dice your white onion, celery stalks, red bell pepper, and green bell pepper, ensuring all the vegetable cuts are uniform and roughly the same size as your chopped hard-boiled eggs.

In a separate medium bowl, combine the mayonnaise, yellow mustard, garlic powder, salt, and black pepper, whisking aggressively for 45 seconds until the mustard and spices form a smooth, pale yellow surfactant emulsion. Forcing the thick condiments to completely blend in a separate bowl stabilizes the fats, ensuring the dressing coats the slick exterior of the cooled noodles uniformly instead of breaking down into greasy pools over time.

Tip the chopped hard-boiled eggs and all your diced vegetables directly into the large bowl with the cooled, seasoned macaroni, then pour the whipped mayonnaise dressing over the top.

Use wide wooden spoons or kitchen tongs to gently fold the ingredients together from the bottom up until the herbs, crisp vegetables, and egg bits are evenly speckled throughout the pasta matrix. Cover the bowl tightly with plastic wrap and transfer it to the refrigerator for a minimum of 2 hours, allowing the starches to chill completely and giving the sweet-and-tangy flavors plenty of time to meld before serving.