Hulk smash! peas and broc

This is a sort of retake on the whole mushy peas arena.  It went with a recent Nadia Lim fish and chip meal, but I've added a couple of extra veges (might as well use up what is in the fridge!).  

This is enough for 2-3 people:

6 florets broccoli and 4 florets cauliflower (or just broccoli), roughly chopped up (stalk and all)
1/2 cup frozen peas 
2-3 cloves garlic, chopped
good handful fresh mint, chopped up
1/2 cup water
2 tbsp butter
salt, herbs and spices of choice (I used salt, pepper and tarragon)

1. Put all ingredients (except butter) in pot.  Put the lid on and steam for a few minutes until just cooked. 
2. Drain excess water. 
3. Add butter and salt/herbs and roughly mash.  Hulk smash!!