Add the flour, salt, and sugar to your food processor. Pulse for a couple of seconds to blend. I like this quick pulse because it spreads the salt and sugar evenly.

Drop in the cold butter cubes and pulse for about 20 seconds. The butter should look like small grains and tiny chunks. Add the egg yolk and pulse again until it blends in.

Add the cold water one tablespoon at a time, pulsing after each spoonful. Stop when the dough gathers into one ball. I fill a glass with ice first, because warm water ruins the texture.

Knead the dough lightly until it forms one smooth ball. Wrap it well or cover the bowl, then chill for 30 minutes. You can do this a day ahead and let it sit out for 30 minutes before rolling.

While the dough rests, toss the thin apple slices with lemon juice, cinnamon, brown sugar, and vanilla. Mix gently so the slices do not break. Let them sit for at least 15 to 20 minutes.

Heat the oven to 350°F and grease the tart pan with a little butter. Knead the dough for a minute, then roll it into a 10 to 11-inch circle. Press it firmly into the pan and trim the extra edge.

Place the lined pan in the fridge for 10 minutes before filling. This short rest helps the crust hold its shape. I never skip it, because it keeps the edges neat in the oven.

Stack handfuls of apple slices from the edge of the pan toward the center. Change direction with each handful for a pretty pattern. Tuck smaller slices into the gaps until the pan is full.

Sprinkle a pinch of sugar over the top and dot with about six small pieces of butter. Bake for 60 minutes until the tart looks golden. Let it cool in the pan.

Melt the sugar in a saucepan over medium heat, stirring often. When it turns amber, take it off the heat and stir in the butter. Add the cream, then the sea salt, and let the caramel cool and thicken.

Once the tart has cooled, lift it out of the pan. Slice it and drizzle with a generous amount of caramel. Finish with extra sea salt and a scoop of ice cream.