My brother in law who just passed from over a decade of fighting cancer also had the same issue.

We pretty much tried to give him things he asked for (coca cola believe it or not!), as well as some liquids packed full of good foods. He was really only taking spoonfuls down to syringes by mouth the last 6 months though.

almond and or coconut milk blended with bananas, other fruits, avocado chicken or beef broths with pureed veggies or just plain

I guess it depends on the person, you also have to remember that their taste buds have probably changed and what he might have loved before he might now hate.

There is a great book I got that offers lots of good ideas how to get nutrient packed things into their diets called:

The Cancer-Fighting Kitchen: Nourishing, Big-Flavor Recipes for Cancer Treatment and Recovery

highly recommended!!!

Cancer cells thrive on glucose, so controlling carbohydrate intake would be a big goal.

Off the top of my head, I am thinking whole fat coconut milk (Native Forest has a good product) or home-made coconut milk (nourishinggourmet.com recipe here), some unsweetened hershey's cocoa powder (more info on my site here) or a few drops of real vanilla, a pinch of cinnamon, and some sort of organic powdered "greens mix" (example here).

Well, I've known people who have broken their jaws and had to eat a liquid diet and they say that liquifying a normal meal actually isn't that bad. Boy, if you could somehow mask the taste of liver in a smoothie, that would be ideal for nutrient density. At the very least, blending meat into it would likely be advantageous.

From what i've read, cancer cells tend to thrive on sugar, so if you do plan on making liquid meal replacements, keep in mind that making them low in sugar would be favorable. Also, i'd keep the protein levels lower as well due gluconeogenesis.

Ensure might not be the best food in the world, but in terms of desperately trying to get easily digestible calories into someone quickly, with at least some nutritional value, it actually isn't bad. When my dad was going through intensive chemo, he drank a lot of these, but later switched to Scandia shakes, which he said tasted better. This was pretty much the only thing he could handle in terms of food, as he had no appetite and digestion issues. He did go into remission for about 4 years, and the shakes were definitely part of the solution.

Besides that, I would recommend bone broths, perhaps mixed with soft-cooked vegetables, depending on what she can tolerate. But there aren't really a lot of calories in this.

Whey and coconut water or oil.

I would also suggest whey with coconut water to mix. If you can add some fruit in that might be nice. I'd also be concerned with the sugar but a little banana or berry might make it taste better.

I'd go with a whey with the least amount of crap in it you can find. IMO that is Jay Robb brand. Seems Bluebonnet makes one that people here like a lot.

If you can afford additional coconut water supplementation I'd do that as well. Look for brands not reconstituted but go with the real thing and buy young coconuts if someone can open them for him.

I also like FED's ideas on working in some coconut milk with a green powder supplement or even real veggies.

Basically we are all giving you the answer to eat real food but blend it up. Hopefully the family has the bandwidth to do something like that. If you must go with something in a can I would look for something low carb and then definitely supplement with coconut water and milk. The ready to drink options are all suboptimal but I'd go with EAS Myoplex Carb Sense Ready To Drink or the EAS AdvantEdge Carb Control Ready to Drink which are readily available in most stores or the SDC Nutrition About Time 100% All Natural Whey Protein Isolate RTD (probably have to order this online). I think the SDC is a better product but not sure if you want to have to order online.