This is a slightly "gourmet" cheap eats, but certain ingredients are optional (I'll mark them with *) and if you leave them out, they'll reduce the cost.

Recipe:
3/4 to 1 lb canned salmon (2 cans @ $3 per can)
1 tbsp dijon mustard* ($0.25) (can sub regular mustard)
1 tbsp capers* ($0.60)
1 small, very finely diced onion ($0.50)
1/4 cup rolled oats ($0.10)
1 tbsp olive oil or canola oil ($0.15)
4 whole grain burger buns ($0.45)
Lettuce ($0.20)
Condiments ($1.00)

If you have a food processor, you can make this in the single bowl. Otherwise, you'll need a blender of some kind of pulse the oats into breadcrumb texture and you'll need to mince the onion and capers very finely by hand.

In the food processor, pulse the oats, onions, capers, and mustard until you have a gritty breadcrumb texture. (Chop and blend all the ingredients by hand w/out the processor). Add in the salmon and pulse until combined. (Or mix by hand).

Form the salmon mixture into 4 equal patties. Remember that because there's no fat in the salmon and because it's precooked, it won't shrink up in the pan, so make the patties the exact size and thickness you want.

Heat the olive oil in a frying pan over medium heat, and cook the patties for about 3 mins a side (enough time to brown on the outside, and cook the onion on the inside).

Serve just like a regular hamburger w/ whatever toppings you want. I like to use Pepperidge Farm's whole grain white buns - they're 6g of protein, 2g of fiber, and only 100 cals each. But whatever you like works.

Like all of my recipes, this one is subject to taste. You can leave out the capers if you want. You can add pepper sauce, or lemon, or really any seasoning you like.

Nutrition (for the patties only):
Based on 4 servings: Cals - 293. Fat - 17.0g. Carb - 5.4g. Fiber - 1g. Protein - 26.1g.
Don't forget to add the value of whatever bun you use, and the condiments. With a bun, lettuce, mustard, etc. a full burgs is usually around 400 calories. You can even add a little mayo and keep the whole burger close to 400.
Full nutritional information available here:Solais Salmon Burgers Recipe - Calorie Count

Cost
$9.25 for 4 servings (although I do think the estimate of $1 for condiments is kind of high). Add cole slaw, or a salad, or chopped veggies and dip as a side, and you can feed 4 people for around $12.

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