What about thanking God for the request you made known to Him?
After all, what is faith?
Mar 11:24 Therefore I say unto you, What things soever ye desire, believe that ye receive them, when ye pray, and ye shall have them.
I change the order of the verse around a little to clarify what Jesus is actually saying.
That is to say, "believe you have received, WHEN YOU PRAY", NOT AFTER it manifests. Believe you have received, regardless of what the situation or circumstance say.
I believe, Paul is telling us to thank God for granting the thing we made known to Him in pray and supplication.
After all, God won't give what you haven't already received, and what better way to express that belief, than to thank and praise Him for the request you are making known or have made known to Him.
Luk 8:17 For nothing is secret, that shall not be made manifest; neither any thing hid, that shall not be known and come abroad.
Luk 8:18 Take heed therefore how ye hear: for whosoever hath, to him shall be given; and whosoever hath not, from him shall be taken even that which he seemeth to have.
Again, according to Mk 11:24, one must believe they already have the thing they asked for or are asking for with thanksgiving, WHEN THEY ARE PRAYING OR DURING THEIR PRAYER.
That is what I see Paul telling us.