How to Make It
Heat oil in a large, high-sided skillet with a tight-fitting lid over medium-high. Sprinkle chicken with 1/4 teaspoon salt and 1/2 teaspoon pepper. Add chicken and sausage to skillet; cook until lightly browned on both sides, 5 minutes. Transfer to a plate. (Do not wipe out skillet.)
Add onion to skillet; cook, stirring occasionally, until onion is translucent, 3 minutes. Add garlic; stir constantly 1 minute. Add couscous; stir often until it is toasted, 2 minutes. Return chicken and sausage to skillet; add tomatoes, stock, thyme, 3/4 cup of the basil, 3/4 teaspoon of the salt, and remaining 1/2 teaspoon pepper. Cover and bring to a boil over high. Reduce heat to medium; simmer until a thermometer inserted in thickest part of chicken registers 165°F, liquid is absorbed, and couscous is tender, 10 to 12 minutes.
Remove chicken from skillet, and let stand 5 minutes. Thinly slice chicken. Stir remaining 1/4 teaspoon salt into couscous mixture. Spoon into shallow bowls; top with chicken and remaining 1/4 cup basil.