Preheat the oven to 425 degrees Fahrenheit.
Rinse the asparagus stalks well under cold water and transfer them to a cutting board. Use a sharp knife to chop off the woody ends of the asparagus and discard. Chop the stalks of asparagus into 2-inch pieces (or bite-sized pieces).
Transfer the chopped asparagus to a large baking sheet then drizzle with avocado oil, sea salt and pepper. Use your hands to toss everything together until the cut pieces of asparagus are coated in oil and seasonings. Spread the asparagus into a single layer over the baking sheet. Roast asparagus on the center rack of the preheated oven for 8-10 minutes for thin asparagus spears, or 12 to 15 minutes for thick asparagus spears. Note that baking for less time results in snappier, crunchier asparagus and baking for more time results in softer asparagus. Gauge the baking time based on your personal preference.
Remove the roasted asparagus from the oven and set it aside to cool.
While the asparagus is cooling, prepare the rest of the recipe.
Mix together the ingredients for the dressing in a small bowl or measuring cup.
Transfer the cherry tomatoes, feta cheese, sliced red onion, kalamata olives, and pistachios to a large mixing bowl.
Once cool, transfer the cooked asparagus to the mixing bowl with the rest of the salad ingredients.
Pour the dressing into the bowl and use tongs or a rubber spatula to toss everything together until well mixed.
Serve asparagus salad alongside your main dish and enjoy.