Lentils are part of the Fabaceae or Leguminosae family: legumes, and as such have no place in the paleo diet, yet are tentatively acceptable as part of what I would call a paleo+ diet.
Legumes as a family represent a wide spectrum. When considering food sources, one does need to look at the whole, the big picture - red kidney beans represent the most toxic end of the spectrum, while lentils represent the least toxic. Beyond paleo Archevore author Kurt Harris makes no mention of legumes, in fact, considers them a useful food source although not ideal.
Legumes MUST be prepared by soaking and then pressure cooking. Canned legumes will have already been soaked and then pressure cooked, or super-heated with steam.
While meat, fish and eggs are on the table, why eat off the plate? Well, lentils could be considered an interested texture or flavour boosting protein calories (include the essential amino acids isoleucine and lysine), as well as acting as a ready source of dietary fibre, folate, Vitamin B1 and a number of trace minerals, notably iron.
Puy lentils lend a unique flavour and pleasant texture to all manner of meals, white fish particularly.
Begin by melting some butter in a skillet and softening a chopped onion or shredded leek. Toss in a clove or two of minced garlic.
Pour in a can of Puy lentils.
Enhance the umami flavours with a touch of tomato purée and a good splash of Worcestershire Sauce. Add a little water and let the lentils simmer.
Meanwhile, prepare the fish and potatoes.
Peel some new potatoes and get them boiling in a pan of water.
Line a steamer pan with tin foil and place the fish portions in there. The foil will protect the fish from the fierce steam as well as enabling the fish to be removed to a flat board for easy transference to the plate.
About 6 minutes before the potatoes are expected to be ready, salt the fish, place the lid on the steamer pan and place over the boiling potatoes.
When ready, reduce the liquid in the lentil skillet, remove the fish steamer pan, drain off the potatoes and add in a good knob of butter to coat the potatoes.
Plate up - lentils in the middle, fish placed gently over and surrounded by buttered boiled potatoes. Sprinkle chopped parsley over.