That can work. We’ve been doing something similar: It’s slow gains (~8kg/year) but it worked for us.

Changes were:

• Increase all meal sizes by ~50% - At least for us it meant every meal went from being “decently filling” to “very (but not overly!) filling”. Don’t repeatedly, find the lining where it still feels OK and don’t cross. There is a risk of loosing your body’s sense of appitite when crossing repeatedly which causes serious long-term problems (eating disorder).
• Use lots of unsaturated fats when cooking: Olive oil is great for this - It doesn’t add much subjective weight to cooked foods, has a lot of kJ/g and doesn’t cause any metabolic disorders if used in consumable quantities (unliked saturated acids or sugars).
• Bananas and peanut butter also rank high on the “decently healthy, high energy scale” and can be incorperated as/into daytime snaks (mini-meals).

All of this from some reading on the subject and self experimentation - I’m not a nutritionist, etc. 😊

haha, fat definitely increases calories, though I find it’s less directly fattening because it doesn’t seem to increase insulin resistance the way simple carbs and sugars do (and insulin seems key to controlling your weight). Though targeting insulin resistance is like aiming to get diabetes, so I don’t suggest it, lol. Still, it gives you a way to really gain weight.

I’m not the most fond of sugar though I think I crave it more since starting HRT. I do typically crave simple carbs like bread, potato chips, etc. - eating more simple carbs can definitely be another way to fatten up (they’re often not as filling either!). I have noticed stress tends to push me towards eating high calorie foods like simple carbs, sugars, and fats, and Robert Sapolsky talks about the mechanism for this in Why Zebras Don’t Get Ulcers.