Peel the kolokasi under running water, wearing kitchen gloves if your skin is sensitive since raw taro can cause mild itching. Cut into 4 cm / 1.5-inch chunks and drop into a bowl of cold water with a splash of lemon juice to stop browning.

Cut the pork shoulder into 4 cm / 1.5-inch cubes and pat dry with paper towels. Drying the pork helps it brown instead of steam in the pot.

Chop the onion, slice the celery, and mince the garlic. Set everything aside near the stove.

Heat 2 tbsp olive oil in a 26 cm / 10-inch dutch oven over medium-high heat. Brown the pork in two batches, about 4 minutes per batch, until deep golden on most sides. Don't crowd the pot or the pork will steam instead of brown. Set the pork aside on a plate.

Add the remaining 1 tbsp oil to the pot. Add the onion and celery and cook 5 minutes, stirring, until soft. Add the garlic and cook 30 seconds until fragrant.

Stir in the tomato paste and cook 1 minute, until it darkens slightly and smells toasty.

Return the pork to the pot with the bay leaves, salt, pepper, and stock or water. Bring to a boil, then lower the heat, cover, and simmer 45 minutes, until the pork starts to soften.

Drain the kolokasi and add it to the pot. Simmer uncovered for 30 to 35 minutes, until the pork is fork-tender and the kolokasi pierces easily with a knife, with a creamy center.

Stir in the lemon juice, taste, and adjust salt if needed. Simmer 5 more minutes.

Remove the bay leaves. Let the stew rest 5 minutes, scatter the reserved celery leaves on top, and serve warm with bread.