EXHIBIT 23.3 CONSENT OF HANIFEN IMHOFF, INC. We consent to the use of our name in the Pennaco Energy, Inc. Registration Statement on Form SB-2 under the heading "BUSINESS." In giving such consent, we do not thereby admit that we come within the category of persons whose consent is required under Section 7 of the Securities Act of 1933, as amended, or the rules and regulations of the Securities and Exchange Commission thereunder. /s/ Hanifen Imhoff, Inc. ---------------------------------------- Hanifen Imhoff, Inc. Denver, Colorado May 4, 1999