Roast ½ cup (70g) cashew nuts in a 350˚F (180˚C) oven for about 20 minutes.
Grind toasted cashew nuts until fine. Combine ground cashews, all-purpose flour, and rice flour in a medium sized bowl. Mix well.
Partially cook ⅓ cup (46g) whole cashew nuts in 350˚F (180˚C) oven for about 10 minutes. Remove and set aside.
Prepare one 2-inch round cookie cutter. Line a baking tray with parchment paper.
In a large bowl, cream butter and powdered sugar until light and fluffy. Add vanilla extract and continue to beat for 30 seconds.
Add flour mixture into the bowl. Mix with a spatula until it resembles breadcrumbs. Then knead gently until dough comes together. Wrap in plastic and chill for 15 minutes.
Place dough in between 2 large pieces of parchment paper. Roll out dough to about ¼ inch thick.
Dip a cookie cutter in flour. Cut out as many circles as possible. Lift cut out cookie dough with a butter knife or spatula and transfer to lined baking tray. Rework trimmed dough until all dough is used up.
Press a partially cooked cashew nut into each cookie dough. Brush top of cookie and cashew nut with egg wash.
Bake in a 350°F (180°C) oven for 10 to 12 minutes or until lightly brown. Transfer to a wire rack to cool completely.