Add frozen fruit to a blender, followed by peanut butter, yogurt, and milk.
Blend until smooth. Add a splash of milk to thin out your smoothie if desired.
Video
Notes
Get yourself a good blender- I use this blender and love it. You don't need a super fancy or expensive blender, just one that will get everything blended together nicely.
If possible, always use frozen fruit for smoothies. It makes your smoothies so much creamier!
Customize your smoothie- add your favorite protein powder, add a veggie like spinach or riced cauliflower (promise you can't taste it), or toss in more sweeteners like honey or maple syrup if you want your smoothie extra sweet. You could also swap the strawberries for raspberries or blueberries.
If your smoothie is too thick, add more milk (or water). If your smoothie gets too thin, I blend in a couple of ice cubes (or add extra frozen fruit) to thicken it back up.