Check the lentils over for stones and give them a good rinse, then set them in a pot with 1 1/2 cups of water, 1/2 an onion, the smashed garlic clove, and the bay leaf.
Bring to a boil, uncovered, then reduce the heat to medium low and simmer with the lid ajar for about 20 minutes.
Start checking the lentils at around the 15 min mark and check every few minutes after that. The lentils should be just barely tender, and still slightly toothsome.
When the lentils are done, fish out the onion, garlic clove, and bay leaf, and drain well.
Place the lentils in a bowl and sprinkle with 1 Tbsp olive oil and 2 Tbsp of red wine vinegar, and a little salt.
Stir, then let stand for 5-10 minutes. Give the lentils a taste and decide if you want to use the rest of the oil and vinegar (I usually do).
Set aside, or refrigerate if you're not making the salad immediately.
Scatter four salad plates with arugula. Place 1/4 of the lentils into the center of each plate, and then drop the cherry tomatoes into place.
Heat 1 teaspoon of olive oil in a large skillet over medium heat.
Place the cubed halloumi into the pan, and fry, turning often, until they are lightly golden brown.
Immediately distribute the halloumi croutons amongst the four plates, then top each with 1 Tbsp of capers.
Drizzle each plate with a small amount of your best olive oil and balsamic vinegar, and a little bit of freshly ground pepper.
Serve, and enjoy!