Whisk together 1 ¼ cup flour with sea salt in a large bowl. Add in cold butter and work ingredients together with your hands until a coarse, sandy looking meal forms.
Add cold water to mixture and continue working and pressing it until the dough melds together. Don't overwork the dough so as to not add too much heat to it.
Shape dough into a flattened square, wrap in plastic wrap, and place in the fridge to chill for at least 30 minutes.
To Make Fresh Peach Cobbler Filling
While the dough chills, peel and slice peaches then combine with brown sugar, flour, cinnamon, and nutmeg in a large bowl and mix until peaches are well coated. Mix in lemon juice.
Melt butter in a large skillet over medium heat and add the filling mixture to the pan. Cook until bubbly and thickened, stirring as necessary (about 5-10 minutes). Remove from heat.
Preheat oven to 350 degrees. Pour prepared filling into a square 8 x 8-inch baking pan. Set aside.
Roll out the chilled dough to about ¼ inch thickness and cut into 8 one-inch strips. Lay the strips over top of peach filling in a lattice or criss-cross pattern.
Brush the dough with beaten egg then sprinkle with granulated sugar.
Bake cobbler for about 45 minutes or until crust is golden brown and filling is thick and bubbly. Allow it to cool and set for at least another 45 minutes then serve.
Notes
PreparationYou don't have to peel the peaches when making peach cobbler using fresh peaches. It is simply a matter of preference.You can prepare this dessert up to three days ahead of time. For the best results, though, I recommend prepping the filling and crust and storing separately then putting them together and baking on the day you will serve it.ModificationsTo make this recipe vegan, substitute the butter and egg with plant based butter and egg products.Canned or frozen peaches will work in a 1:1 ratio for fresh peaches. If you opt to use canned peaches, skip step two under the filling instructions.You can use store bought pie crust dough to save time, if needed.Tool SubstitutionsYou can combine the pie crust dough using your hands, a dough blender or a food processor.If you don't have a rolling pin, a wine bottle (empty or full) can work as a good substitute in a pinch!StorageStore leftover peach cobbler in the fridge, in an airtight container or covered with aluminum foil or plastic wrap. It will keep for up to one week.To freeze, allow the cobbler to cool to room temperature then double wrap it aluminum foil and freeze. It will keep for up to three months.