While you wait for water to boil, prepare all the vegetables since this is the most time-consuming prep work. Dice the celery stalks into 1/4-inch pieces, finely dice the onions, dice the green peppers into 1/4-inch pieces, and shred the carrots finely. I recommend using a food processor for the onions and carrots to save time when working with this volume—it cuts prep time significantly without affecting the final texture.

Bring a large pot of salted water to a boil (use about 1 tablespoon of salt per gallon of water). Add the 8 lb of elbow macaroni and cook until just tender, about 8-10 minutes—check the package directions, but aim for pasta that's cooked through but still has a slight firmness since it will soften further as it cools and sits in the dressing. Drain the pasta thoroughly and rinse it with cold water until completely cooled, stirring occasionally to ensure even cooling and to prevent clumping.

In a large mixing bowl, whisk together the mayonnaise, sugar, mustard, vinegar, salt, black pepper, celery seed, and smoked paprika until fully combined and smooth. The dressing should taste slightly more seasoned than you'd want the final salad to be, since the pasta and vegetables will dilute the flavors. I like to taste a small spoonful and adjust the vinegar or salt if needed—this is your chance to get the balance of tangy and savory just right before everything comes together.

Add all the prepared vegetables from Step 1 directly into the dressing bowl and stir thoroughly to coat everything evenly. Make sure the vegetables are distributed throughout the dressing—they should all be well-coated and the dressing should be evenly mixed. This step can be done a few hours ahead if needed, and the vegetables will soften slightly and release their juices into the dressing.

Add the completely cooled macaroni from Step 2 to the vegetable-dressing mixture and fold everything together gently but thoroughly, using a large spoon or your hands. Make sure every piece of pasta is coated with dressing and the vegetables are evenly distributed throughout. This is a large volume, so take your time to ensure everything is mixed well.

Transfer the macaroni salad to serving containers or a large bowl and refrigerate for at least 2 hours—this allows the flavors to meld together and the pasta to absorb the dressing properly. Before serving, give it a good stir and taste for seasoning, adding a pinch more salt, pepper, or vinegar if needed. The salad can be made up to a day ahead and actually tastes better the next day as the flavors develop further.