PREHEAT oven to 350°F. Grease baking sheet.
CUT squash in half stem to tip and remove seeds. Cut a small slice from outer side of each squash to help them stand up straight when serving. Place cut-side-down on prepared baking sheet.
BAKE for 40 to 50 minutes or until tender when pierced with a fork.
WHILE squash is baking, heat oil in a large saucepan over medium-high heat. Add leeks and carrots; cook, stirring occasionally, for 5 minutes or until leeks are soft. Stir in water and quinoa. Bring mixture to a boil. Reduce heat to medium-low; cover. Cook for 12 minutes or until quinoa is tender. Remove from heat; stir in pesto and salt.
TURN squash halves cut-side-up; spoon quinoa mixture into cavities. Sprinkle with cheese. Return to oven for 5 minutes or until heated through.
