Once the taco salad is fully assembled, I do recommend serving it right away so the lettuce is nice and fresh and the Doritos are nice and crispy. However, different taco salad components can be prepped ahead of time and stored in the fridge. First, the beef/bean mixture will keep in an airtight container for 3-4 days. You can serve it cold or reheat it with a drizzle of oil in a skillet. This is perfect for meal prep! Second, the tomato and pepper can be chopped and stored in the fridge for up to 2 days.