To make the burgers
Preheat the oven to 190ºC/375ºF/gas mark 5. Line a large, rimmed baking pan with unbleached parchment paper.
Put the black beans and salsa in a medium-sized bowl and mash using a potato masher or large fork until well combined.
Put the bread chunks and cumin in a blender and process into coarse crumbs.
Add the breadcrumbs to the black bean mixture and stir to combine. Stir in the rolled oats and mix to combine. If the mixture seems dry, stir in another heaped tablespoon of salsa and mix to combine.
Scoop up a generous ½ cup of the black bean mixture and put it on the prepared pan. Form it into a burger, shaping it with clean hands, then flattening it slightly. Continue in this manner to make five more burgers.
Bake for 20 minutes. Flip the burgers and bake for 8 to 12 minutes, or until golden.
To make the fries
Preheat the oven to 200ºC /400ºF/gas mark 6. Line a large, rimmed baking sheet with unbleached parchment paper.
Cut each potato into 10 to 12 thick wedges. Arrange the potato wedges in an even layer on the prepared sheet. Sprinkle with the chilli powder, garlic powder and salt.
Bake for 30 to 40 minutes or until very crispy and golden, turning once. Let cool 5 minutes and season with more salt, to taste.