To make a creamy dip suitable for tostones, or simply to spoon over rice, beans, or meat, the technique is a little different. You start with roasted garlic cloves, which provide a bit of emulsion to the final product. Fresh cilantro is essential, and replaces most or all of the fresh oregano.
Cover your garlic cloves with enough olive oil to cover. I like to make a larger batch, because roasted garlic is delicious in Italian food, Cuban food, or just smeared on fresh bread, but you can also put them in a tiny mason jar inside a pan (for easy handling) if you only want to roast a small quantity. Place them in the oven (you can put them in while something savory cooks) and roast 30ish minutes at 300-400 degrees. When the oil begins bubbling watch them for browning and pull out when they're barely beige.
Mash cloves slightly in immersion blender cup, then add citrus juices and blend. Pour in oil a little at a time, blending to make an emulsion (similar to making mayo, but it will be thinner.) Stir in chopped fresh herbs, cumin if desired, and salt and pepper to taste.
This dipping sauce really requires fresh herbs. Feel free to add some fresh oregano, parsley or thyme to the cilantro, for a less traditional but still delicious green sauce. If you have a little porch space, I strongly recommend growing your own oregano and thyme. During blooming season, the flowers are delicious. (That's the purple in my pictures.)