Methemoglobinemia can result from ingestion of nitrite- or nitrate-containing foods. Here, we report a case where an adolescent girl and her father developed clinically significant methemoglobinemia after ingestion of “homemade” beef jerky prepared with sodium nitrate salt purchased at a local grocery store. Both had palpitations, dyspnea, and visible mucosal cyanosis. The daughter had a methemoglobin level of 44.2% and the father's methemoglobin level was 34.2%. Prompt recognition of methemoglobinemia is important for initiating antidotal therapy with methylene blue.