Place cooked couscous in a large bowl and set aside.
Pour 2 tablespoons of olive oil into a medium sauté pan and warm over low-medium heat.
Add the onions and cook for 2-3 minutes.
Toss in the red pepper and carrots, and sauté for an additional 2 minutes.
Add the asparagus and cook for 1 minute.
Remove from heat, and place in the bowl with the couscous.
In the same pan, add another 2 tablespoons of olive oil over medium heat.
Add the sliced mushrooms and sprinkle with a bit of salt and pepper.
Cook the mushrooms for about 4 minutes, stirring occasionally, until they are tender.
Reduce the heat to low, then add the minced garlic.
Sauté for 2 minutes, and then add the mixture to the couscous.
Toss the couscous mixture until the ingredients are incorporated.
Mix the 1 tablespoon of olive oil with 1 tablespoon lemon juice, lemon zest, or preserved lemon, and dill.
Pour the dressing over the couscous, add the scallions and cranberries (and feta, if using it), and toss everything together.
Season generously with salt and pepper.
Serve chilled, warm, or room temperature.