Trim the liver by removing the white connective tissues and possible bile spots if any.
Slice the onion, crush the garlic, and black pepper.
Combine liver, onion, garlic, black pepper, leaf, thyme and salt in a pan.
Add water.
Place the lid on and bring it to boil. This should be quick, depending on the amount of liver of course.
Simmer it until there are almost no pink visible when the liver is cut.
Remove the basil leaf.
Scoop everything into a food processor. However, the liquid is precious, mind not to pour everything inside at once. If we have added too much water, our spread could turn to be too soft at the end.
Add the optional cognac or sweet wine.
Mix well.
Add the butter by two spoonfuls and mix well. Taste the spread and adjust the recipe accordingly. However, butter is optional, it will soften the strong charater flavor of liver and makes it more enjoyable for everyone, not just the hardcore fans.
Serve the spread out. It fits lovely into silicon cupcake holders too.
If we choose to store them in the fridge longer than a day, melt butter and pour on top to create an airtight top layer.