Heat 1/4 cup of the olive oil in a large skillet over medium heat.

Add garlic and cook until it starts to turn golden brown, about 2 minutes.

Add Swiss chard, 1/4 teaspoon of salt and 1/4 teaspoon of pepper and cook until just wilted, about 4 minutes, then remove to a colander and drain well. Set aside to cool.

Meanwhile, put mustard, apple cider vinegar and red wine vinegar into a bowl and whisk together.

Slowly add remaining 1/2 cup olive oil and canola oil to the mixture in a slow and steady stream while whisking constantly. Set vinaigrette aside.

Squeeze out and discard as much liquid as possible from the swiss chard.

Add approximately 1/4 cup of the vinaigrette to the Swiss chard in a small bowl and mix together.

Season flank steak all over with the remaining 1/2 teaspoon salt and 1/4 teaspoon pepper.

Arrange Swiss chard on the inside of the flank steak, spreading it out evenly.

Top with cheese and slowly roll up the flank steak.

Secure roll with kitchen twine, tied at 1-inch intervals down the length of the steak.

Preheat the oven to 375°F.

Spray flank steak all over with canola oil cooking spray.

Heat a large skillet over medium high heat and add flank steak.

Cook, turning occasionally, until golden brown all over, then transfer steak to a baking dish.

Roast in oven for about 15 to 20 minutes, or until the meat reaches an internal temperature of 130°F.

Set aside to let rest for 5 to 10 minutes, then slice into pinwheels and serve with the remaining vinaigrette on the side.