Everything comes together quickly, so measure out everything before starting. Place all dry ingredients (flour and spices) into a small bowl and place it near the stove. Place the 2 tbsp tomato paste and 2 cups broth near the stove as well.
In a medium-sized pot over medium heat, warm the 3 tbsp oil until it’s hot enough that a light sprinkle of the flour/spice mixture sizzles on contact. This might take a couple of minutes, so be patient.
Once it’s ready, pour in the flour and spice mixture. While whisking constantly, cook until fragrant and slightly deepened in color, about 1 minute. Whisk the tomato paste into the mixture, then slowly pour in the broth while whisking constantly to remove any lumps.
Raise heat to medium-high and bring the mixture to a simmer, then reduce heat as necessary to maintain a gentle simmer. Cook, whisking often, for about 5 to 7 minutes, until the sauce has thickened a bit and a spoon encounters some resistance as you stir it. (The sauce will thicken some more as it cools.)
Remove from heat, then whisk in the vinegar and season to taste with a generous amount of freshly ground black pepper. Add more salt, if necessary.