Put all of the ingredients into a saucepan and bring to the boil. Remove from the heat and allow to cool. Once cold pass and immerse the grouse for between 6 and 12 hours.
Take the birds from the brine and rinse under cold water for a couple of minutes.
Take a 150ml can and fill it ⅔ with your preferred beer. Impale the grouse on the can and cook in a hot oven for about 12-15 minutes depending on the size of the bird.
Remove from the oven and allow to rest on the case.