2 lbs fingerling potatoes, cut into 3/4 inch chunks
2 Tbs lime juice (1-2 limes)
½ tsp salt
¼ tsp ground cayenne pepper (optional)
1 plum tomato, chopped
1 small red onion, diced small
1 medium cucumber, diced very small
Scallions for garnish (optional)
Put potatoes in a pot and cover with water. Cover pot, bring water to a boil. Lower the heat to a rolling boil and cook for 15 to 20 minutes, until potatoes are easily pierced with a fork. Drain and set aside to cool.
Split the avocado in half, remove the seed and scoop into food processor. Add the lime juice and salt and puree until smooth, scraping down the sides with a spatula as needed. Once smooth and creamy, add the tomato and onion. Pulse until they are incorporated but not completely blended. You should still be able to see the tomato and onion.
Put the potatoes and cucumbers in a large mixing bowl and mix them up. Add the dressing and mix well. Taste for salt and spice. Wrap tightly and chill until ready to use. Top with scallions, if you like.