Imam Jafar Sadiq (asws) narrates:
“I have been told there are some who go for the Ziarat of Hussain (asws) whilst carrying different kinds of food with them, including akhbisah (a type of dessert made from mashed dates) and other similar desserts.
However, they would never have gone to the graves of their loved ones whilst carrying any of these things.”
Ref. Kamil ul Ziaraat

Abul Mada narrates:

Aba Abdullah Imam Jafar Sadiq (asws) asked me, “Do you go to the grave of Aba Abdullah al Hussain (asws)?”
I replied, “Yes.”
Imam (asws) said, “Do you take different kinds of food with you?”
I replied, “Yes.”
Imam (asws) said, “If you were going to the graves of your own fathers and mothers, you would never do a thing such as this.”
I asked, “Then what should we eat?”
Imam (asws) replied, “Bread and milk.” Abul Mada added, “Abdul Kareem ibn Amr al Khathami narrated the he said to Aba Abdullah Imam Jafar Sadiq (asws), “May I be sacrificed upon You! Some people perform the Ziarat of the grave of Hussain (asws) and take delicious foods with them.”
Imam (asws) said, “If they were going to the graves of their own mothers and fathers, they would have never done a thing such as this.”
Ref. Kamil ul Ziaraat

Imam Jafar Sadiq (asws) narrates:

“Performing the Ziarat of Imam Hussain (asws) is better than not performing it. But there are occasions when it is better to not perform His Ziarat than to perform it.”
I exclaimed, “You broke my back!”

Imam (asws) replied, “By Allah! When you go to the graves of your fathers you are saddened and grief-stricken but when you go for the Ziarat of Hussain (asws) you carry various kinds of food with you. No! It is better for you to not go unless you go while being disheveled and covered with dust.”
Ref. Kamil ul Ziaraat

Imam Jafar Sadiq (asws) narrates:

“When you want to perform the Ziarat of Hussain (asws), do so while being sorrowful, heartbroken, grief-stricken, disheveled, covered with dust, hungry, and thirsty. For Hussain (asws) was martyred while being sorrowful, heartbroken, grief-stricken, disheveled, covered with dust, hungry and thirsty.

After you perform His Ziarat, ask Him for your needs and then leave. Do not settle in Karbala.”
Ref. Kamil ul Ziaraat