Position racks in upper and lower thirds of oven; preheat to 325 degrees F. Line 2 large baking sheets with parchment paper or silicone baking mats.

Whisk condensed milk and almond extract in a large bowl until combined. Pulse almonds in a food processor (about 10 quick pulses) until broken unto small pieces. Stir the almonds, coconut, 1/2 cup cranberries and 1/2 cup pistachios into the condensed milk mixture.

Beat egg whites and salt in a medium bowl with an electric mixer on medium-high speed until soft peaks form, about 1 minute. Fold 1/2 cup of the egg whites into the coconut mixture. Add the remaining egg whites, gently folding into the mixture until just combined. Drop 1 teaspoon of dough onto a prepared baking sheet and top with another teaspoon of dough, making a double-tall macaroon. Repeat with the remaining batter, spacing the macaroons 1 inch apart.

Bake the macaroons, switching the pans back to front and top to bottom halfway through, until the coconut is lightly golden, 18 to 22 minutes (sweetened coconut will brown faster than unsweetened). Let cool on the pans on a wire rack until cool to the touch, 30 minutes.

Optional garnish: Place 1/2 cup chocolate chips in a microwave-safe bowl and melt in the microwave on Medium in 30-second bursts, stirring after each burst to ensure even melting, until completely melted. (Alternatively, melt the chocolate in a double boiler over hot water, stirring constantly.) Stir the remaining 1/4 cup chips into the melted chocolate until smooth. Drizzle or spoon the melted chocolate over the top of each cooled macaroon; sprinkle with cranberries and pistachios. Let the chocolate dry completely before storing or packing.

MAKE AHEAD TIP: These macaroons are best eaten fresh, but will keep for up to 5 days at room temperature.