Step 1

Line a medium plate with parchment paper. Using a 1 1/2-tablespoon cookie scoop, portion out 6 scoops of white lotus paste and drop onto the parchment. Freeze the paste until solid, at least 45 minutes or overnight (cover if freezing overnight).

Step 2

Make the water dough: In a medium mixing bowl, whisk to combine flour, matcha powder, and sugar. Add shortening and water, breaking up the shortening with your fingers and kneading the dough until smooth, 3 to 4 minutes. Pat the dough into a thick disc, wrap in plastic, and refrigerate for 30 minutes.

Step 3

Make the oil dough: In a medium mixing bowl, combine flour and shortening, breaking up the shortening with your fingers and kneading until smooth, 1 to 2 minutes. Pat the dough into a thick disc, wrap in plastic, and refrigerate for 30 minutes.

Step 4

Preheat the oven to 400°F and line a large rimmed baking sheet with parchment paper.

Step 5

Divide both the water and oil doughs into three equal pieces (6 pieces total) with a bench scraper (for accuracy, weigh with a digital scale, if you have one). On a lightly floured surface, roll each portion of the oil dough into a smooth ball. Roll out the water dough into 4-inch rounds. Working with one pair at a time, center a ball of oil dough ball on a water-dough round and pinch the edges together to cover completely. Place the ball seam-side down and flatten with your palm. Continue to dust with flour if sticking. Roll out the dough into a long oval, about 8 inches long, and roll up into a coil, starting with a short edge. Flatten the dough with your palm again and roll out into an 8-inch long oval. Roll the dough up into a coil, starting with the short edge. Cut the dough in half crosswise with a sharp knife. Place the pieces of dough cut-side up, and flatten with your palm. Roll out a piece into a 4-inch round and place the filling in the center. Pinch the edges of the dough together to fully seal. Place the mooncake on the prepared baking sheet and repeat with remaining dough and filling, spacing each at least 2 inches apart.

Step 6

Bake until flaky and slightly golden, 25 to 28 minutes. Transfer the baking sheet to a wire rack and allow the mooncakes to cool on the sheet. Serve warm or at room temperature.

Step 7

Soak the seeds in water for 8 hours or overnight. Drain and rinse the seeds. Some of the seeds might have small green sprouts inside, try your best to remove as many of these as you can.

Step 8

In a medium saucepan, combine soaked seeds and enough water to cover the seeds by 2 inches. Bring the water to a simmer and continue to simmer until the seeds are tender, 45 minutes to 1 hour. Drain the seeds and rinse under cold water.

Step 9

In the bowl of a food processor, combine seeds and sugar. Blend until smooth. In a medium nonstick frying pan over medium-low heat, add the puree and canola oil. Stir constantly with a flexible spatula until the oil is blended in and the color deepens, 8 to 10 minutes. Transfer the white lotus seed paste to a heat proof container and allow to cool.