Preheat oven to 200 degrees C/Gas 6.
1) Coat a large baking tray with cooking spray.
Arrange asparagus on baking tray and spray with cooking spray. Season with salt and black pepper. Roast 10 minutes. Top the asparagus with almonds and roast 5 more minutes, until fork-tender and almonds are golden brown. Remove from the oven and set aside.
2) Heat oil in a large skillet over medium heat. Add onion, garlic and sugar and cook 3 minutes, until soft stirring with wooden spoon. Add chicken and saute 3 to 5 minutes, until golden brown on all sides. Add lime juice and carefully, off the heat, add the rum. Return to the heat and add lime zest, salt, pepper and bring to a simmer.
3) Simmer for 3 minutes, until chicken is cooked through, about 12 to 15 minutes. Serve chicken, garnished with mint, over couscous with the almond topped asparagus on the side.