Start by making the dough: Place the flours and salt in the bowl of a stand mixer fitted with a paddle attachment. Mix on low speed to combine.

Add the room temperature, cubed vegan butter to the mixer bowl. On low speed, combine with the flour until the butter is fully incorporated into the dough, around 2-3 minutes, scraping down the sides of the bowl as needed. 

In a small bowl, whisk the oil and water together. With the mixer on a low speed, slowly pour the liquid mixture into the butter and flour mixture and mix until the dough just comes together, 2-3 minutes. The dough should be soft and malleable.

Divide dough into two equal parts, cover tightly in plastic wrap and let it rest in the refrigerator for a minimum of 1 hour, or up to overnight.

Meanwhile, make the filling: In a large skillet, heat the oil over medium heat. Add onion and sauté until lightly brown, 3-4 minutes. Add the ground beef to the skillet and use a wooden spoon to break up any lumps, continuing to cook over medium heat.

Add the walnuts to the meat and stir until they begin to toast and turn fragrant. Add the spices, salt and pepper to the skillet and mix well to combine. Let the meat mixture cook for another 3-4 minutes. Turn the heat off, remove the skillet from the stovetop and let the mixture cool for ten minutes.

Assemble the sambusak: Place the egg-wash in a bowl and the sesame seeds on a flat plate. Line a baking sheet with parchment paper. Divide the dough into 40 equal, walnut-sized pieces (around .75 oz or two tablespoons each) and lightly roll into balls. Meanwhile, preheat the oven to 375º F.

Lightly roll each ball out with a rolling pin until it is a thin disk, 2” in diameter. Fill each with a heaping teaspoon of the meat mixture, placing it in the center of the round of dough.

Fold filled disks of dough in half, bringing the edges together. To make a traditional sambusak edge, use your forefinger and your thumb to crimp the edges and fold over all the way around the edge. Otherwise, use a fork to crimp all around the edges of the sambusak, pressing the tines into the dough.

Dip the top of the sambusak in the egg-wash, then immediately dip it in the sesame seeds to fully cover the top. Place the dipped sambusak sesame seed-side up on the baking sheet and continue to make more sambusak, placing them ¼ inch apart until the baking sheet is full.

Bake the sambusak for 15-18 minutes, until just brown around the edges. Serve immediately.

Alternatively, you can freeze the sambusak and bake when ready. Freeze them first on a baking tray, then transfer them to freezer-safe Ziploc bags. Bake the frozen sambusak straight from the freezer, without allowing them to thaw, adding an extra 5-6 minutes to the baking time.