Add <quantity>250<unit>g</unit></quantity> of all-purpose flour, <quantity>125<unit>g</unit></quantity> of water, and <quantity>2<unit>g</unit></quantity> of salt to a large bowl

Mix until everything is combined

Knead with your hands into a pliable, but not too soft dough

Cover and set aside for 5m

Knead until perfectly smooth

Cover and set aside for 30m

Use a mandoline or a knife to cut <quantity>1</quantity> japanese cucumber into fine strips. Transfer it to a bowl

Add <quantity>1<unit>tsp</unit></quantity> of salt and mix to spread it

Crack <quantity>3</quantity> eggs into a bowl and whisk to combine

Add <quantity>2<unit>tbsp</unit></quantity> of vegetable oil to a preheated skillet over medium heat

Add the egg and stir until it's scrambled hard

Transfer the scrambled eggs to a bowl. Squeeze the juice out of the cucumber and add it to the eggs

Add <quantity>½<unit>tsp</unit></quantity> of white pepper, <quantity>½<unit>tsp</unit></quantity> of salt, <quantity>1<unit>tsp</unit></quantity> of soy sauce, and <quantity>1<unit>tsp</unit></quantity> of toasted sesame oil

Stir until combined. The cucumber and egg filling is ready

Form the dough into a roll and cut it into two equal parts

Shape each half into a cilinder with <quantity>2<unit>cm</unit></quantity> diameter

Trim the edges and cut it into <quantity>15</quantity> equal parts, rotating the cilinder 90° after each cut. Repeat with the other half of the dough

Flatten each piece lightly with the palm of your hand keeping them as round as possible. Sprinkle a bit of flour if it sticks to your hand

Sprinkle the dough pieces with flour and roll them out with a rolling pin until they are the size of the palm of your hand. Keep the center slightly thicker than the edges

Place a piece of dough on the fingers of your non-dominant hand and add a portion of the filling

Fold the dough and lightly press the edges to close it

Use your index fingers and thumbs to seal the dough and push the filling to the center of the dumpling. Place them on a lightly floured plate

Fill a large pot with water and bring to a boil over high heat

Place the dumplings in the boiling water and cook until they float and slightly puff up

Drain them. The cucumber & egg jiǎozi is ready

Enjoy these amazing jiǎozi!