01 -
Toss the flour, sugar, salt, and chilled butter in your food processor. Pulse for about a minute so you see bits like small peas. Now, pour in ice water bit by bit and pulse until everything just sticks together.
02 -
Drop the dough on a floured counter. Squish it into a fat circle, wrap up snug, and park it in the fridge for at least an hour.
03 -
Grab a mixing bowl and stir up the rhubarb, strawberries, brown sugar, lemon juice, zest, cornstarch, and vanilla seeds till everything's coated well.
04 -
Pull the cold dough onto a floured surface. Roll it out into a rough big round, about half a centimeter thick, then lay it on a parchment-lined baking tray.
05 -
Scatters oats all over the dough. Heap the fruit in the center but leave a 4 cm edge all around. Fold that dough border over the filling, scrunching at the corners to look messy but awesome.
06 -
Slide the tray with the ready galette into your freezer. Let it firm up for about 15 minutes.
07 -
While the galette's chilling, get your oven warming up at 190°C.
08 -
Pull the galette from the freezer. Brush the crust with your egg and milk mix and shower on lots of coarse sugar.
09 -
Pop it in the hot oven. Bake till the edges go deep golden and the fruit filling bubbles away—should take 40 to 45 minutes.
10 -
Let it sit a few minutes, then slice it up and top with a scoop of vanilla ice cream while it's warm.