Integrating with an existing Azure OpenAI model with an API Key

I've looked far and wide for an answer to this, but I am trying to configure connecting to an existing model deployed in Azure Foundry. It is an OpenAI model. But I cannot find an option that allows me to connect to an existing model with an Api Key for permissions.

I have tried to follow the documentation (https://aspire.dev/integrations/cloud/azure/azure-openai/#connect-to-an-existing-azure-openai-service) but I consistently get asked for Azure subscription details so it can provision the model.

Is there a sample somewhere, or has someone successfully configured this ... integrating with existing models in Azure Foundry? Or do I just go with configuring this in each project and forget getting Aspire to manage the integration?