1. Preheat oven to 325°F (165°C). Wrap the outside of a 9-inch springform pan with 2–3 layers of heavy-duty foil; lightly grease the inside.

2. Make the crust: mix crumbs, melted butter, sugar, and salt until it resembles wet sand. Press firmly into pan (and 1 inch up the sides). Bake 8–10 minutes until fragrant; cool 10 minutes.

3. Beat cream cheese on medium-low until smooth. On low speed mix in sugar, sour cream, cornstarch, vanilla, lemon zest, and salt just until combined.

4. Beat in eggs one at a time on low speed until just incorporated (avoid whipping in air).

5. Pour filling over crust. Set springform in a large roasting pan; pour hot water into the pan to reach halfway up the sides.

6. Bake 55–65 minutes, until edges are set and the center jiggles like gentle Jell-O.

7. Turn off oven, crack door, and let cheesecake rest inside 1 hour. Remove, unwrap, cool to room temp. Chill uncovered 1 hour, then cover and chill at least 4 hours or overnight.

8. Blueberry topping: simmer blueberries, sugar, and lemon juice over medium heat until juicy. Stir in cornstarch slurry; cook 1–2 minutes until glossy and slightly thickened. Cool completely.

9. Release springform, transfer to platter, spoon topping over center, and slice with a hot, dry knife.