Step 1

Combine the cabbage, lettuce, apples, carrots, cauliflower, and scallions in a large serving bowl. Toss several times so that the carrot ribbons tangle with the cabbage shreds and lettuce leaves, and the cubes of apples and bits of cauliflower settle throughout rather than at the bottom of the bowl.

Step 2

In a small bowl or spouted measuring cup, briskly whisk together the mayonnaise and oil until completely smooth. Add the sugar and mustard and whisk again. Finally, whip in the vinegar, salt, and pepper until the whole of it emulsifies into one dressing. Pour the vinaigrette over the salad, scatter the pepitas into the bowl, and toss again to combine everything. Serve immediately.

Step 3

If you plan on having leftovers, hold off on the vinaigrette and pepitas, adding those per serving to prevent the salad from becoming soggy and the pepitas from losing their crispy crunch (You can just reserve a portion of the salad for saving, too, and dress the rest for serving immediately). Refrigerate the undressed salad in an airtight container for up to 4 days and store the pepitas in a zip-top bag or container outside of the fridge.