Fully bake your pie crust according to the recipe instructions. You can use my flaky pie dough recipe, or a store-bought pie crust. Alternatively, use a graham cracker crust for a completely no-bake pie. Let it cool.
Wash and dry your strawberries, then hull them and slice them in half.
Put half of the strawberries in a bowl for later, then put the remaining half in a medium saucepan along with the sugar and 1 tablespoon of the water.
Heat the strawberries on medium heat, stirring occasionally, until the mixture is hot and the berries start to release juices. At this point, you can mash them slightly with a fork or potato masher (it's easier to do once they are warm). You don't need to mash them completely to a pulp, just help to break them down a bit and the heat will do the rest.
Let the strawberry mixture boil, stirring occasionally, until the liquid has reduced slightly and has a syrupy consistency. This should take about 5-8 minutes of boiling. Don't reduce the liquid so much that the mixture becomes thick and jammy.
In a small bowl, mix the remaining cold water with the cornstarch to make a slurry, make sure all the cornstarch has incorporated in the water and there are no lumps. Gradually pour the cornstarch mixture into the mashed strawberries, stirring constantly but not vigorously. The strawberry mixture will begin to thicken almost immediately. Keep boiling for 1-2 minutes until it has noticeably thickened, there are big bubbles bursting on the surface, and it is no longer cloudy from the cornstarch.
Once the mixture has thickened, remove from the heat and stir in the lemon juice.
Let the strawberry mixture cool until it is no longer hot to the touch (about 15 minutes). Then, pour it over the remaining strawberries and gently stir until all the berries are evenly coated. It's important not to do this when the mixture is too hot, as it can cause the fresh berries to release extra juices, which will mess up the consistency of the filling.
Pour the strawberry filling into the baked pie crust, and spread it out evenly. Feel free to arrange the top strawberries into a pretty pattern, or just line them up to look a bit neater.
Let the strawberry pie cool to room temperature, then chill, uncovered, for at least 4 hours before serving, preferably overnight.
Strawberries - Use fresh strawberries for this pie, not frozen. Frozen strawberries contain extra moisture that can cause your pie to be runny. Important Tips:Cornstarch is very fickle. It is important to pay attention to the recipe steps or your pie may not set properly. Make sure you mix the cornstarch into cold water first, then gradually pour it into the strawberries and let it boil for 1-2 minutes (but no longer than this). The strawberry mixture should be reduced slightly, but not so much that there is no free liquid for the cornstarch to bond with. See the 'Strawberry Pie Science' section in the blog post for more info on this. Don't add the lemon juice at the start, it needs to be added after the cornstarch has thickened the mixture, as the acidity can stop it from working properly.