Preheat oven to 350°F. Spray a 9-inch pie dish very well with cooking spray; set aside.

In a large, microwave-safe bowl, melt the butter (about 1 minute on high power).

Wait momentarily before adding the egg to avoid scrambling it. Add the egg, brown sugar, and vanilla extract, and whisk until smooth.

Add the flour and salt, stirring until just combined (do not overmix).

Turn the batter out into the prepared pie dish and smooth the top lightly with a spatula. Bake for about 10-12 minutes or until the edges firm up slightly and the center has begun to set. It’s not fully baked yet, but will return to the oven.

Remove the pie dish from the oven. Evenly sprinkle ¾ cup chocolate chips over the crust, then sprinkle with the coconut.

Drizzle the sweetened condensed milk and caramel sauce evenly over the pie (don’t worry about being too precise).

Return the pie to the oven and bake for about 25 minutes or until there’s slightly bubbling near the edges and the center looks more set. Watch closely in the last 10 minutes to avoid burning the coconut, caramel, and condensed milk.

Allow the pie to cool in the dish on a wire rack.

While the pie cools, melt the remaining ¾ cup chocolate chips in a microwave-safe bowl, heating for 1 minute on high power. Stir and heat in 10-second increments until smooth.

Drizzle the melted chocolate in long vertical lines, spaced about ½-inch apart, using a spoon or pastry bag.

Allow the pie to continue cooling on the wire rack for at least 4 hours (or overnight) before slicing and serving.