Place the cumin seeds in a small frying pan and stir over medium heat for 2 minutes, or until they darken a shade. Remove from the heat. Finely grind half of the cumin seeds in a coffee grinder or with a mortar and pestle.

In a blender or food processor, combine the egg, mustard, salt, garlic, and the ground cumin seeds. Process briefly to blend. With the motor running, add the vegetable oil in a slow, steady stream. Pour in the lemon juice and then slowly add the olive oil until the aioli is emulsified. If the mixture seems too thick, add a spoonful or two of water. Scrape the aioli into a bowl and stir in the whole cumin seeds. Cover and refrigerate.

To make the steak:
In a small bowl, mix the oil, salt, garlic, and pepper. Spread on both sides of the steak. Cover and refrigerate up to overnight.

Preheat the grill or broiler. Grill or broil the steak for 3 to 4 minutes on each side for medium-rare. Remove the steak from the heat and let it sit for a few minutes. Slice very thinly across the grain and serve with the aioli on the side.

Per serving:
Effective carbohydrates: 1.2 g; Carbohydrates: 1.5 g; Fiber: 0.3 g; Protein: 42.7 g; Fat: 58 g; Calories: 701