If you are using frozen Puff Pastry like me, remove dough from package and keep it out to defrost. It takes 15-20 mins depending on your room temperature.
In meantime prepare filling and onions. To make filling, add dry cashew nuts, coconut milk, cumin powder, coriander powder, salt, ginger & garlic paste, pepper to a blender and blend to smooth paste.
Keep prepare filling aside and saute onion. Peel onion and cut in half, thinly slice and keep aside. In a medium sized pan, add cooking oil and when oil is hot, add sliced onions and cook on medium flame. Add salt and pepper and cook till onions turn translucent but still holds the shape
When both filling and onions are ready and puff pastry has defrosted, tartlets can be arranged to bake.
Open defrosted pastry dough on flour dusted surface and roll out a bit ( not too thin ). Using your tart pan as reference, cut out the dough and place it on tart pan. Lightly press to the shape of pan, add prepared cashew filling to 3/4th of tart pan and top with cooked onions. Repeat the same process for all tartlet pans.
Bake at 400F for 20-25 mins or till pastry puff turns light brown in color.