how to pass a list of double quoted strings as an azure pipeline variable input to terraform task?

I am trying to pass a list of strings as an azure pipeline variable to a terraform task.

I have a variable created for the pipeline called such that ips = [\"1.1.1.1\", \"2.2.2.2\"] and I can access this in the azure pipeline using $(ips)

I want to pass this variable as mentioned here in the official terraform documentation: terraform apply -var='image_id_list=["ami-abc123","ami-def456"]' to the terraform plan task

here is my terraform plan section of the yaml:

        - task: TerraformTaskV1@0
          inputs:
            provider: 'azurerm'
            command: 'plan'
            commandOptions: '--var-file variables/$(Build.SourceBranchName)/$(Build.SourceBranchName).tfvars  -var=''allowips=$(ips)''' 
            environmentServiceNameAzureRM: $(linked_service)
          displayName: 'Terraform plan'

when the pipeline runs, it fails at the terraform plan step with the error -

terraform plan --var-file variables/dev/dev.tfvars -var='allowips=[ \1.1.1.1", "2.2.2.2" ]'
stat \1.1.1.1", "2.2.2.2" ]': no such file or directory
##[error]Error: The process '/opt/hostedtoolcache/terraform/0.12.28/x64/terraform' failed with exit code 1

I have also tried various combinations of for declaring the azure pipeline variable like: ips = ["\"1.1.1.1\", \"2.2.2.2"\]

which also gives the same error -

terraform plan --var-file variables/dev/dev.tfvars -var='allowips=[ "1.1.1.1", "2.2.2.2" ]'
stat "1.1.1.1", "2.2.2.2" ]': no such file or directory
##[error]Error: The process '/opt/hostedtoolcache/terraform/0.12.28/x64/terraform' failed with exit code 1

I have tried to a lot of combinations of setting quotes or double quotes on the commandOptions value and also the ips variable but I am getting the same errors (or valid terraforms error).

It seems the first double quote in the azure variable seems to causing some issues. Any pointers o how to pass a list of double quoted strings as an azure pipeline variable input to terraform task is much appreciated. Thanks!

edit -

I hardcoded the values directly in the yaml but still getting errors.

commandOptions: '--var-file variables/$(Build.SourceBranchName)/$(Build.SourceBranchName).tfvars -var=''allowips=[\"1.1.1.1\", \"2.2.2.2\"]'''

and it basically does not accept the ip values and asks for a manual entry:

/opt/hostedtoolcache/terraform/0.12.28/x64/terraform plan --var-file variables/dev/dev.tfvars -var='allowips=[\1.1.1.1", "2.2.2.2"]'
var.allowips
  Enter a value: 

again it seems there is a problem around the first double quote.