Pierce squash several times with a fork. Place squash in microwave oven on paper towels. Microwave, uncovered, at HIGH 4 minutes, rearranging squash after 2 minutes. Let stand 5 minutes.
Cut each squash in half lengthwise; scoop out and discard pulp, leaving 1/4-inch-thick shells. Invert squash shells onto paper towels, and set aside.
Coat a small nonstick skillet with cooking spray; place over medium-high heat until hot. Add minced green onions and chopped pepper; saute until tender. Remove from heat; add corn and next 3 ingredients.
Spoon vegetable mixture evenly into squash shells. Place stuffed shells in a 13- x 9- x 2-inch baking dish coated with cooking spray. Cover with heavy-duty plastic wrap and vent. Microwave at HIGH 4 to 6 minutes or until thoroughly heated. Place squash on a serving platter. Garnish with a green onion curl, if desired.