To start the dressing: Place the minced shallot in a pint jar and add the vinegars and salt. Let rest while making the salad.
To make the salad: Preheat a medium-sized skillet coated with olive oil over medium heat. Drain the halloumi if needed and cut it into 8 slices. The halloumi slices should be at least ¼” in thickness. I prefer slightly thicker slices so that some moisture is retained in the cheese after frying.
Add the halloumi to the heated skillet and fry until golden brown, 1-2 minutes, depending on how hot your pan is. Flip and fry the other side. Remove from the skillet, transfer to a cutting board, and cut each strip into 3-4 pieces. I like triangles to give a bit of visual contrast.
Slice the tomatoes in halves and quarters and place them in a bowl with the halloumi.
To finish the dressing: Add the olive oil, mustard, and black pepper to the shallot jar. Seal the jar with a lid and shake vigorously, or, to truly emulsify, use an immersion blender until the dressing is silky. Taste and adjust the olive oil to achieve the desired vinegar punch.
To finish the salad: Drizzle the dressing over the tomato and halloumi mixture, tossing until everything is well coated.
Crush the crackers using a mortar/pestle, or place them in a bag and crush them with a rolling pin. The goal is to have a range of sizes, including some that have been finely crushed. Sprinkle the crushed crackers over the halloumi salad before serving.