Configure TLS - Traefik 2 and Kubernetes

Hi all. I've configured Traefik 2 on Kubernetes like so:

This seems to work with the below simple test:

apiVersion: traefik.containo.us/v1alpha1
kind: IngressRoute
metadata:
  name: ra-demo
  namespace: ra-demo
spec:
  entryPoints:
    - http
  routes:
    - match: Host(`ra-demo.domain.com`)
      kind: Rule
      services:
        - name: ra-demo
          port: 8080

But how can I add TLS to this configuration? Our certificates are in Kubernetes secrets. Thanks.