Gaining weight?

Make high calorie smoothies:
Milk, almond milk or coconut milk
protein powder
almond, peanut or cashew butter
fruit of choice. Depending on how much of each intermediate you use, these smoothies can have anywhere from 200 to over 500 calories.

To gain weight, eat about 1800 calories per day and focus on strength training instead of cardio.

Eat a lot and do squats.

Dont even touch cardio. seriously. Lift weights and do enough that it hurts you. Every week do more and more weight in your lifts. You should never stagnate.

Seriously? Ignore the advice of idiots on the internet. It's good to do cardio, it's good to lift. It's good to be healthy. I do agree with adding in some weights/resistance if you aren't already.

I'd say get into nuts, avocados, meat (if you eat it), bananas, healthy shakes (personally I love ones loaded with fruits).

^^ No need for name calling here. The point is to try to help the newbie!

I'd suggest lifting 3-4x a week and if you want to do cardio, do HIIT once a week to keep your heart healthy (no more than 20 minutes). And eat what was suggested by other people. Great ideas there!

Add cheese to everything - its why I still have 21lb to lose Seriously, all the high fat/high protein advice wil put on calories and help you have the stamina to do more weight training.

Dont even touch cardio. seriously. Lift weights and do enough that it hurts you. Every week do more and more weight in your lifts. You should never stagnate.

Seriously? Ignore the advice of idiots on the internet. It's good to do cardio, it's good to lift. It's good to be healthy. I do agree with adding in some weights/resistance if you aren't already.

I'd say get into nuts, avocados, meat (if you eat it), bananas, healthy shakes (personally I love ones loaded with fruits).

Cardio will make the OP's goal to gain weight more difficult. Lifting at a calorie surplus will make it easier.

OP, I second the suggestion that you lift heavy weights. Read New Rules of Lifting for Women for all the information.

2 miles per week of cardio (as pointed out in the OP) will have a very slight negative effect on gaining. That effect can be overcome by drinking one glass of skim milk per week.

Some light cardio will help your fitness and help keep the fat off as you gain. It is highly fat partitioned and has almost zero recovery cost, it won't impact your strength training in a negative way (could actually improve it).

But it has to be light cardio, walking, slow jogging, etc...; partaking in the HIIT fad is about the single worst thing you could do for your potential gains. Not only does it burn up the calories (which can be overcome by eating more), the calorie partitioning is highly carb based (which is the fuel you need for strength training), and it has a significant recovery cost that will negatively impact your strength training and gains (and when gaining weight less muscle gain means more fat gain).

Muscle loss from cardio isn't a factor until your sessions are long (and intense) enough to completely run your muslces out of nutrients (2 hr+, if you aren't marathon training, don't worry about it), or you aren't eating enough to support your activity level (see all the people on MFP "not eating their exercise calories back" or eating half back to "be safe", yeah, don't be one of those people or let your thinking be influenced by them).

Do what I do when my appetite falters.

100g protein powder, 100g maltodextrin and 30g peanut butter and a banana. Around 1000 cals in a single shake, downed in seconds.

The only cardio I really do is light jogging. How much of that is ok per week? I want to do more than 2 miles, but I keep getting told it's a bad idea. I'm def not trying to train for a marathon.

I run about 10 miles a week and walk another 10 miles a week, and gain without issue (very clean too, about a 3:1 muscle to fat ratio).