Strawberry-Vanilla Swirled Frozen Pops

Mash strawberries in a large bowl with a potato masher or a fork. Transfer to a 12-inch nonstick skillet along with sugar and lemon juice and boil over medium heat, stirring occasionally, until slightly thickened, about 10 minutes. Transfer to a bowl, then freeze, uncovered, until cold, about 10 minutes. Transfer ice cream to a microwave-safe bowl and microwave at 30 percent power in 10-second intervals, stirring, until softened, about 50 seconds total. Spread evenly in a 13-by 9-inch baking dish and freeze while strawberry mixture chills. Dollop tablespoons of strawberry mixture all over ice cream, then swirl it gently through ice cream with a spoon. Spoon into molds (or into cups) and add sticks. Freeze until firm, about 1 1/4 hours (and up to 4 days, covered).