Prep your pan. Heat oven to 325°F. Wrap a 9-inch springform pan tightly in two layers of heavy-duty foil (this prevents leaks). Lightly grease the bottom and sides. Set aside.
Make the crust. Mix graham cracker crumbs, sugar, and melted butter until it looks like wet sand. Press evenly into the bottom of your prepared pan using a flat-bottomed glass or measuring cup. Bake for 8 minutes, then set on a wire rack to cool while you make the filling.
Beat the cream cheese. In a stand mixer fitted with the paddle attachment (or with a hand mixer), beat the softened cream cheese on medium speed until completely smooth and no lumps remain — about 2 minutes. This step matters more than most people realize; skip it and your cheesecake will have grainy spots.
Add sugar and dry ingredients. With the mixer running, slowly pour in the granulated sugar. Add milk powder, flour, and vanilla. Beat on low until just combined — don't overmix now or you'll incorporate too much air.
Incorporate the eggs. Crack the eggs into a separate bowl (this way you can fish out any stray shell pieces). Beat them lightly first, then add to the cream cheese mixture one at a time, mixing on low just until each egg disappears before adding the next — about 30 seconds per egg. The batter will be thick and glossy.
Pour and bake. Spread the filling over your cooled crust, smoothing the top with a spatula. Place in the oven and reduce heat to 275°F. Bake for 1 hour 10 minutes. The edges should look set but the center should still have a slight jiggle — like Jell-O that's almost firm — when you gently shake the pan.
Cool slowly. Turn off the oven, crack the door open with a wooden spoon handle, and let the cheesecake cool inside for 1 hour. This gradual cooling prevents cracking better than any other trick I've tried.
Chill thoroughly. Remove from the oven and cool completely at room temperature (about 30 minutes), then refrigerate uncovered for at least 6 hours or overnight — 8 is ideal. The longer it sits, the cleaner your slices will be.
Make the strawberry topping while chilling. In a medium saucepan over medium heat, combine sliced strawberries, sugar, and lemon juice. Cook for 5-7 minutes until berries start to break down and release their juices. Stir in the cornstarch mixture and cook another minute until glossy and thickened. Let cool completely — it will thicken more as it cools.
Serve. Remove the springform ring. Slice with a hot, clean knife (dip in warm water between cuts for neat slices). Spoon strawberry topping over individual portions or drizzle across the whole cake. Serve within 3 days for best texture.
