Marinate

• Slice the liver into individual portions. Place into a plastic bag with a ratio of 2:1 soy sauce to calamansi or lemon juice. Set this mixture aside for up to two hours. The marinade will displace some of the moisture in the liver, removing some of the strong liver flavor.

Cook the Liver

• Heat oil or rendered fat in a large skillet. Remove the liver from the bag, retaining the marinade. Sear the pieces of liver over high heat for 1 to 2 minutes per side until the internal temperature reaches 160 degrees Fahrenheit for beef and pork or 165 degrees for chicken. Do not overcook the liver because of textural considerations. Do not crowd the pan; sear the liver in batches if necessary. Remove the liver to a serving platter.

Prepare the Sauce

• In the same skillet you used to sear the liver, heat extra oil if necessary and cook the thinly-sliced onions until soft. Add the garlic and cook for a short time until browned. Add the leftover marinade, deglaze the pan by scraping up the brown bits, and simmer until the sauce reduces and thickens.

Serve

• Pour the onion-garlic sauce over the cooked liver. This flavorful sauce will complement the liver and mask the liver's strong taste. Serve liver steak warm; its texture is best when freshly cooked.