-
1
To make the ketchup, heat the oil in a small nonreactive saucepan over medium heat.
-
2
Add the garlic and chile flakes and cook for 1 minute.
-
3
Add the ketchup and oregano and cook for 2 minutes.
-
4
Remove from the heat and stir in the vinegar and basil and season with salt and pepper.
-
5
Transfer to a bowl and let cool to room temperature or cover and refrigerate for up to 1 day.
-
6
Bring to room temperature before serving.
-
7
To make the fricos, combine the cheese and flour in a bowl.
-
8
Heat an 8-inch nonstick pan over medium-high heat.
-
9
Add 3 tablespoons of the cheese mixture and cook until light brown on the bottom.
-
10
Turn over with a heat-proof silicone spatula and continue cooking for another 10 to 15 seconds.
-
11
Remove to a plate to cool.
-
12
Wipe out the pan with a paper towel and repeat to make 3 more fricos.
-
13
Divide the meat into 4 equal portions (about 6 ounces each).
-
14
Form each portion loosely into a 3/4-inch-thick burger and make a deep depression in the center with your thumb.
-
15
Season both sides of each burger with salt and pepper.
-
16
Cook the burgers, using the oil (see page 16).
-
17
Place the burgers on the bun bottoms.
-
18
Add some of the arugula to each burger, top with the fricos, and then add a dollop of the ketchup.
-
19
Top with the bun tops and serve immediately.
