First you need to determine whether you want to file an Objection to Claim or if your complaint MUST be filed as an Adversary Proceeding.

Rule 3007. Objections to Claims

(a) Objections to Claims. An objection to the allowance of a claim shall be in writing and filed. A copy of the objection with notice of the hearing thereon shall be mailed or otherwise delivered to the claimant, the debtor or debtor in possession, and the trustee at least 30 days prior to the hearing.

(b) Demand for Relief Requiring an Adversary Proceeding. A party in interest shall not include a demand for relief of a kind specified in Rule 7001 in an objection to the allowance of a claim, but may include the objection in an adversary proceeding.