Add 1 cup of water, basmati rice and a pinch of salt to a small saucepan and bring to a boil. Cover, reduce heat to low, and cook until the water is absorbed, around 15 minutes.
Wash and dry all the vegetables. Thinly slice the sugar snap peas and scallions. Dice the cucumber. Trim about an inch off the ends of the asparagus. Pick and roughly chop the mint leaves. Halve the avocado, removing the pit. Slice lengthways. Juice the lemon.
In small bowl, add just 1 tbsp of the lemon juice, the dried parsley and the ranch dressing. Add a pinch of salt and pepper. Stir to combine.
Heat a large skillet with 2 tsp of olive oil over medium-high heat. Add the asparagus and let cook, undisturbed, until charred in places, 3 - 4 minutes.
Sprinkle the asparagus with salt and pepper, toss, and cook until tender crisp, another 2 minutes.
Fluff the cooked basmati rice with a fork and transfer to a large bowl. Add the sliced sugar snap peas, scallions, diced cucumber, chopped mint leaves, remaining lemon juice and 2 tsp olive oil. Gently toss to combine. Taste and add extra salt and pepper as necessary.
Divide the vegetable pilaf between large plates or bowls and top with the cooked asparagus, sliced avocado and (optional) pistachios. Drizzle with the herbed ranch dressing.