Add flour, sugar, and salt to a food processor and pulse to combine.
Add cold butter and pulse until crumbly with pea-sized pieces.
Add ice water one tablespoon at a time until dough just comes together.
Flatten the dough a bit, wrap, and chill for at least 30 minutes.
Roll out dough and cut heart shapes.
Mix filling ingredients. Add filling to half the hearts, leaving edges clear.
Brush edges with plant milk, top with remaining hearts, and crimp with a fork.
Poke holes in tops and brush lightly with plant milk.
Bake at 375°F for 20 minutes until lightly golden. Cool completely.
Whisk glaze ingredients and drizzle over cooled Pop-Tarts.