Preheat oven to 350°. OPTIONAL: line a jumbo or regular muffin tin with paper or silicone liners.
Crush the cookies with a rolling pin, or put them in the food processor to get ⅔ cups. Add to a small bowl with melted butter and sugar if using.
Reserve a few tablespoon crumb mixture for topping. Divide the remaining crumb mixture between the wells of a jumbo muffin tin or 8 wells of a regular muffin tin.
Bake at 350° for about 10 minutes. Place on a cooling rack to cool.
Tangerine Curd
Zest 1 of the tangerines using a citrus zester or box grater. Cut the tangerines in half, remove seeds and juice to get approximately 1 cup juice.
Put the zest and sugar in a food processor fitted with the steel blade. Pulse a few times until the zest and sugar are mixed together.
Add the butter and pulse to combine. Add the eggs, 1 at a time, pulsing until blended.
Pour the mixture into a medium saucepan and stir in the tangerine juice.
Cook over low heat until thickened, about 10 minutes, stirring constantly.
Remove from heat and cool.
Tangerine Ginger Tartlets
Divide the curd evenly between the crusts. Sprinkle with the reserved crumbs.
Refrigerate until the curd is firm, 2-3 hours.
To serve: gently slide a knife around each tartlet then gently push the knife into the center to pop the tartlet out of the pan. If using liners just remove from pan.
Slide on to individual plate and serve.
Notes
If you do not have the Ginger Oat Grahams use ⅔ cups crushed graham crackers with ⅛ - ¼ teaspoon ginger (depending on how much ginger you like).