How can I see which instances are associated with an EKS cluster?

I can use the AWS CLI to list cluster names and describe clusters, but how can I see which instances are actually in the cluster?

aws eks list-clusters --region us-east-1

    "clusters": [
        "foo-cluster",
        "bar-cluster"
    ]
}

aws eks describe-cluster --name foo-cluster

{
    "cluster": {
        "name": "foo-cluster",
        "arn": "arn:aws:eks:us-east-1:12345:cluster/foo-cluster",
        "createdAt": 1554068824.493,
        "version": "1.13",
        "endpoint": "https://12345.abc.us-east-1.eks.amazonaws.com",
        "roleArn": "arn:aws:iam::12345:role/foo-cluster12345",
        "resourcesVpcConfig": {
            "subnetIds": [
                "subnet-45678",
                "subnet-34567",
                "subnet-23456",
                "subnet-12345"
            ],
            "securityGroupIds": [
                "sg-12345"
            ],
            "vpcId": "vpc-12345"
        },
        "status": "ACTIVE",
        "certificateAuthority": {
            "data": "zubzubzub="
        },
        "platformVersion": "eks.2"
    }
}