- If you are not using fresh corn, you can skip infusing the stock as above but I recommend warming it before adding in stage below.  
- As stock is infusing/warming, peel and dice the onion, potatoes and carrot and cut the celery in similar-sized pieces. All should be relatively small - I suggest making the carrot, celery and onion similar size to the corn kernels, and the potato slightly bigger to allow for slightly different cooking times. 
- Once all are prepared, melt the butter in a medium pot over medium heat and add the onion. Cook until the onion is starting to go translucent, around 3 - 5 minutes, but without letting them burn. Add the carrot, potato and celery and cook a few more minutes. 
- Add the flour and stir to coat the vegetables and absorb some of the excess butter.  
- Add the stock, cover and bring to a simmer. Reduce heat and cook for around 5 - 10 minutes, depending on size of vegetable pieces, until the potato and carrot are tender to a knifepoint (but not overly soft). 
- Add the corn and crab meat, mix through and cook a minute or two more. Add the cream, warm through a minute but do not let it boil then check seasoning before serving.