Patatas Bravas

3/4 cup plus 3 tablespoons olive oil
1 large yellow onion, chopped
1 large tomato, chopped
2 large garlic cloves, chopped
2 tablespoons good quality paprika
2 tablespoons all-purpose flour
1 cup vegetable stock
1 1/2 pounds Russet potatoes, peeled and cut into 1-inch cubes

Paprika Sauce:

Heat 3 tablespoons oil in heavy medium skillet over medium-low heat
Add onion, tomato, garlic, and paprika and cook 10 minutes, stirring occasionally
Add flour and cook 3 minutes, stirring constantly
Gradually add stock and bring to boil Reduce heat and simmer until mixture is reduced to 2 cups, about 8 minutes
Transfer mixture to blender and puree until smooth. Season with salt and pepper

Heat remaining 3/4 cup oil in heavy large skillet over medium heat
Add potatoes and cook until golden brown and cooked through, stirring occasionally, about 20 minutes
Transfer potatoes to paper towels and drain
Divide potatoes among plates. Bring sauce to simmer and spoon over potatoes.
Serve with aioli on the side.

Variation: for a healthier, albeit less authentic, version, oven roast the potatoes instead of frying