Is "learning", used as a noun, Denglish?

The English term "learning" is being used as a noun in German language, describing the process of learning something about a specific topic. ("Das Learning war, kein Wasser ins brennende Fett zu schütten." / "The learning was to not put water into the burning grease."). Is this a case of Denglish?

Solution 1:

The sentence

The learning was to not put water into the burning grease

is unnatural in English. Or it's obsolete. The Oxford English Dictionary (OED) reports that learning was once used to refer to

What is learnt or taught:
a. a lesson, instruction.

But not anymore. So, yes, your sentence is Denglish.

Today we would probably say the lesson learned or the lesson:

The lesson (or: lesson learned) was to not put water into the burning grease.

However, we can use learning as a verbal-noun. The main definition is

The action of receiving instruction or acquiring knowledge (OED)

This is close to your description "the process of learning something about a specific topic."

as in

The learning of German is a hard and tortuous endeavor.

But we would probably use it more often without an article:

Learning German is an arduous task.

Learning can also refer to

Knowledge, esp[ecially] of language or literary or historical science, acquired by systematic study; also, the possession of such knowledge, learnedness. (OED)

For example, Alexander Pope wrote

A little Learning is a dang'rous Thing. (OED)

Today we sometimes say a person knows just enough about [some topic] to be dangerous.

Solution 2:

If you're asking whether it is used the same way in English, then the answer is no. If you'd like a comparable idiom in English:

take-home message

The use of learning as you described in German reminds me of the word for parking lot in France: "parking".