Basic Sofrito - cooking recipe

Ingredients

2 tablespoons unsalted butter (or olive oil)
12 scallions, white and light green parts only, finely chopped
1 small yellow onion, finely chopped
1 small tomatoes, cored and finely chopped
1/4 cup cilantro leaf, chopped
salt and freshly groung black pepper, to taste

Preparation

Melt the butter or heat the oil in a saucepan on medium heat. Add the remaining ingredients and cook, stirring often, until the onion is soft and golden and the tomato is broken down and pasty. This should take about 10 minutes. Transfer to a bowl and set aside to cool.