Line a 9x13-inch baking sheet with parchment paper or a silicone mat; grease lightly if using parchment.
In a medium, heavy-bottomed saucepan, combine granulated sugar, water, light corn syrup, and fresh lemon juice. Stir over medium heat until sugar dissolves, then stop stirring.
Add hulled and chopped strawberries. Bring to a boil over medium-high heat and clip in a candy thermometer, ensuring it doesn’t touch the pan bottom.
Cook without stirring until mixture reaches 2456F (1186C), about 15–20 minutes, watching thermometer closely.
Remove from heat and immediately pour onto prepared baking sheet, spreading to a 1/4–1/2-inch thickness.
Let candy set at room temperature for 2–3 hours (or chill 30–60 minutes), then lift off parchment and cut into squares with an oiled knife or kitchen shears.
If desired, dust pieces lightly with powdered sugar to prevent sticking.