Cook then mash the potatoes, then set aside to cool. Or use 2 cups of prepared mashed potatoes.
In a large bowl add the mashed potato. Stir in the melted butter and the egg. Mix until smooth. Then add the rice flour, corn starch, salt and baking powder. Mix until a smooth dough forms. Wrap the dough ball in plastic wrap and place in the refrigerator for 1/2 hour.
Pre heat oven to 450 F.
In a small bowl mix the poppy seeds, sesame seeds, dried garlic and onion, basil and salt, until well combined.
Cut the dough into 8 pieces. Roll into balls and flatten with lightly (rice) floured fingers. Place onto a parchment paper lined baking sheet. Brush with melted butter then sprinkle with the everything mixture.
Bake for 15 minutes. Remove from the oven then brush with melted butter once more.