Heat the oil in a saucepan and add the onions. Stir to coat them with oil, then cover and cook them over a low heat for 5-10 minutes until they start to soften, stirring occasionally.
Add the pumpkin, bacon, and cumin to the pan. Stir, then cover and simmer for 10 minutes, stirring occasionally.
Add the stock, raise the heat and simmer, uncovered, for 20 minutes, or until the pumpkin is tender.