If my belly didn't hang so much I bet I would be

I don't think I could ever not be aware of my obesity.

Heavy cream is almost pure fat so It will cause you to gain.
How much a person gains depends on their body so there is no magic math formula that some seem to claim there is.
Some will say X number of calories will result in Y number of pounds gained over some prescribed time frame.
Gaining doesn't work that way so leave your assumptions for other things

As I was gaining I ate a lot and pretty much all day some days.
I got used to eating that way and would over shoot my goal weight by 20 lbs or so.
I binge ate quite a bit on the weekends and after a few years of over eating I had gained way more than I ever expected to.
I developed a compulsive overeating habit/disorder and it has caused me to continue to gain.
I can control it most of the time but I still snack some if I am around food so I try to keep snacks away during the day.
I still eat way too much come meal time LOLOL

If you want to gain just increase your food intake.
Try to eat bigger portions at each meal.
Forcing the process can cause issues like heartburn and the like.
There is no science or magic food,pill to gain weight.
You body chemistry is unique to you and what works for some may not work for you.
I will say if you like milkshakes or ice cream have some before going to bed so you are sleeping and not putting out any energy while the calories are adding up.
Its a commitment and it takes effort to gain so thinking it will be easy is not the way it is.
Keep increasing the amount of food you eat on a daily basis and start snacking more in between meals helps too.
There will be some here that say for X amount of calories you eat Y number of pounds you will gain,this is not how it works. People that say that are not gainers and have no idea what they are talking about
By eating more your body's metabolism will slow down eventually and you will notice your weight going up but it may take a few months for this to happen so don't get discouraged just keep it up because it takes time .

So he wants a fat feeder or does he want a fat feedee?
Perhaps he hasn't figured out how to make a complete sentence that is coherent or he doesn't have his terminology correct.

I grew up listening to classical music Bach,Brahms etc.Good stuff and I still enjoy it.
Growing up I listened to most anything and liked it.
Pop R&B R&R some country.
Metal is more my thing and when I was little my Mom said I would love it when Black Sabbath songs would play on the radio.
Something about metal speaks to me and its really hard to explain.
I started playing guitar around 12 years old and while I can play classical,pop,country metal is where my soul is.
Played in hair metal,prog metal,thrash metal bands for years so thats my music.

Any good dark German beer.
I like a brand called Spaten.
Sooo tasty too

eat what you like just more of it.
There is no magic food that will make you gain weight faster.
Drinking heavy cream adds lots of fats so you can try that.
If you like milkshakes start having those several times a day.
Eat a bowl of ice cream before bed that has worked for me.
Gaining weight takes time and effort and you have to wait for your body to adjust to the extra food and calories. Once your metabolism slows down then you will start to gain.
Its different for everybody so if someone says X number of calories eaten in a day equals Y number of pounds gained doesn't know what they are talking about.

Any one that says X number of calories in equals Y number of pounds gained is full of it.LOL
I really never kept records of how much I gained at any one time.