In the stovetop pressure cooker (mine is a 4-quart one), heat the oil.
Add the black cumin, cloves, cardamom, star anise and bay leaves and saute, stirring, for about a minute over medium-high heat.
Add the onions and saute until they start to change color and turn lightly golden.
Add the ginger and garlic and saute for a minute.
Add the potatoes, then the carrots, cauliflower, and green beans. Mix well and cook, stirring occasionally, about 3 minutes over medium heat. Add the fried onions and stir well.
Add the biryani masala and the coconut milk along with the mint and coriander leaves. Mix well.
Add the water and salt to taste. You need to add enough salt at this time because you won't be able to mix in the salt after the biryani cooks.
Add the lemon juice and the rice. Mix well.
Pop on the pressure cooker lid, make sure it's set to pressure-cook (and not to steam), and let it come to pressure. (On my Fagor pressure cooker, there's a little yellow button that pops up when the cooker reaches pressure).
After pressure is reached, cook for three more minutes, then take the pressure cooker off heat.
Wait for the pressure to be released, and then slide open the lid carefully. Be sure you follow manufacturer instructions for your cooker.
Fluff the rice with a spoon and serve hot with some raita.
*I used a stovetop pressure cooker for this recipe, but if you have an electric one, go ahead and use it. If your cooker has a "brown" function, you can proceed just as directed for the stovetop version, but if not, you will have to do part of your cooking on the stovetop-- up until the step where the vegetables are sauteed and cooked and the fried onions are stirred in. Then transfer the veggies to the electric cooker, add the biryani masala, coconut milk, lemon, rice, and salt. Set your pressure cooker timer to five minutes or as directed by your manufacturer.