Adjust rack to middle position and preheat oven to 450 degrees. Wash and dry all produce. Mince garlic. Trim and discard bottom ends from asparagus; cut stalks crosswise into 3-inch pieces. Strip thyme leaves from stems; discard stems and roughly chop leaves. In a small pot bring vegetable stock to a simmer over medium heat.
Toss garlic, asparagus, tomatoes and half the thyme on a baking sheet with a drizzle of olive oil and pepper. Roast, tossing halfway through, until asparagus is tender and tomatoes burst, 12-15 minutes.
Meanwhile, trim and thinly slice scallions, separating whites from greens (optional – we omitted onions). Melt 2 tbsp of light butter in a medium pot over medium heat. Add scallion whites and cook, stirring, until fragrant, 1 minute.
Add couscous and remaining thyme to same pot. Cook, stirring, until grains are lightly toasted, 1-2 minutes.
Pour simmering stock into pot with couscous mixture. Reduce to a low simmer, cover, and cook until tender, 6-8 minutes. Drain any excess liquid from pot, if necessary.
Fluff couscous with a fork; season with pepper. Divide between plates, then top with roasted veggies. Sprinkle with almonds, feta and scallion greens. Enjoy!