Feeding with a spoon

This is my first baby and she is going to be 5 months next week. She had her first avocado today, I mixed it with breastmilk. She likes it but started cry after awhile. It wasnt as fast as her bottle and not what she used to. So I ended up putting the avocado into a bottle with more breastmilk. My question to mommies with this experience is how long did it take for your baby to get used to the spoon? To realize the food is on the spoon.