For cooking Ox Tongue it's best to rinse in cold running water
for a hour or so, next place in a deep stock pan, cover with cold
water, a large onion, 2 large carrots, a few sticks of celery all
roughly chopped, some thyme, bay leaf, few white peppercorns 6
whole garlic cloves and a few drops of white wine vinegar.
Bring to the boil, skim off any white proteins on the surface
then reduce heat to a simmer and cook for a minimum 2 hours 30
minutes until tender when pierced with a skewer at the thickest
point.
Leave the tongue to cool in the broth for an hour or so.
To peel the outer skin off the tongue simply place your index
finger at the throat part of the tongue, and gently work your
fingers underneath all the way to the tip end, peel and missed bits
and discard all of this.
Next step is either place in a classic tongue press and chill
for 24 hours , or return the tongue to the broth and chill for up
to 3 days.