How to use NSWAG to generate Options request with CORS header response for APIGateway

Question

I am developing a C# REST API and I am using NSAG to generate OpenApi 3.0 doc which I can import to AWS APIGateway. Now to enable CORS, I need to add OPTIONS endpoint configuration as described in aws documentation here: https://docs.aws.amazon.com/apigateway/latest/developerguide/enable-cors-for-resource-using-swagger-importer-tool.html I am able to add the below configuration by hand into the generated specification and when I import into AWS APIGateway api, it works. But I am not sure how to automatically generate this configuration.

"options" : {
        "produces" : [ "application/json" ],
        "responses" : {
          "200" : {
            "description" : "200 response",
            "headers" : {
              "Access-Control-Allow-Origin" : {
                "type" : "string"
              },
              "Access-Control-Allow-Methods" : {
                "type" : "string"
              },
              "Access-Control-Allow-Headers" : {
                "type" : "string"
              }
            }
          }
        },
        "x-amazon-apigateway-integration" : {
          "type" : "mock",
          "responses" : {
            "default" : {
              "statusCode" : "200",
              "responseParameters" : {
                "method.response.header.Access-Control-Allow-Methods" : "'*'",
                "method.response.header.Access-Control-Allow-Headers" : "'Content-Type,X-Amz-Date,Authorization'",
                "method.response.header.Access-Control-Allow-Origin" : "'*'"
              },
              "responseTemplates" : {
                "application/json" : "statusCode: 200"
              }
            }
          },
          "requestTemplates" : {
            "application/json" : "{\"statusCode\": 200}"
          },
          "passthroughBehavior" : "when_no_match"
        }
      }
    },

The stripped down version of current generated specification is here:

{
  "x-generator": "NSwag v13.15.10.0 (NJsonSchema v10.6.10.0 (Newtonsoft.Json v13.0.0.0))",
  "openapi": "3.0.0",
  "info": {
    "title": "My API",
    "description": "My API",
    "version": "1.0.0"
  },
  "servers": [
    {
      "url": "https://my.dummy.url"
    }
  ],
  "paths": {
    "/Contacts": {
      "get": {
        "tags": [
          "Contacts"
        ],
        "description": "Gets list of Contacts the current user has access to.",
        "operationId": "Contacts_GetContacts",
        "parameters": [
          {
            "name": "skip",
            "in": "query",
            "required": true,
            "schema": {
              "type": "integer",
              "format": "int32",
              "default": 0
            },
            "x-position": 1
          },
          {
            "name": "take",
            "in": "query",
            "required": true,
            "schema": {
              "type": "integer",
              "format": "int32",
              "default": 100
            },
            "x-position": 2
          }
        ],
        "responses": {
          "200": {
            "description": "",
            "content": {
              "application/json": {
                "schema": {
                  "$ref": "#/components/schemas/ContactList"
                }
              }
            }
          }
        },
        "security": [
          {
            "jwt-rsa-custom-authorizer": []
          }
        ],
        "x-amazon-apigateway-integration": {
          "connectionId": "[APIGATEWAY_VPCLINK_ID]",
          "httpMethod": "GET",
          "uri": "[MYAPI_HOST]/api/publicapi-Contacts",
          "responses": {
            "default": {
              "statusCode": "200"
            }
          },
          "passthroughBehavior": "when_no_match",
          "connectionType": "VPC_LINK",
          "type": "http_proxy",
          "cacheKeyParameters": [
            "method.request.querystring.skip",
            "method.request.querystring.take"
          ]
        }
      }
    },
  },
  "components": {
    "schemas": {
      "ContactList": {
        "allOf": [
          {
            "$ref": "#/components/schemas/PaginatedListOfContact"
          },
          {
            "type": "object",
            "additionalProperties": false
          }
        ]
      },
      "PaginatedListOfContact": {
        "allOf": [
          {
            "$ref": "#/components/schemas/ListBaseOfContact"
          },
          {
            "type": "object",
            "additionalProperties": false,
            "properties": {
              "TotalRecords": {
                "type": "integer",
                "format": "int32"
              },
              "Skip": {
                "type": "integer",
                "format": "int32"
              },
              "Take": {
                "type": "integer",
                "format": "int32"
              },
              "RecordsReturned": {
                "type": "integer",
                "format": "int32"
              }
            }
          }
        ]
      },
      "ListBaseOfContact": {
        "type": "object",
        "additionalProperties": false,
        "properties": {
          "Data": {
            "type": "array",
            "nullable": true,
            "items": {
              "$ref": "#/components/schemas/Contact"
            }
          }
        }
      },
      "Contact": {
        "type": "object",
        "additionalProperties": false,
        "properties": {
          "ContactKey": {
            "type": "string",
            "nullable": true
          },
          "FullName": {
            "type": "string",
            "nullable": true
          },
          "WorkPhoneNumber": {
            "type": "string",
            "nullable": true
          },
          "MobilePhoneNumber": {
            "type": "string",
            "nullable": true
          },
          "EmailAddress": {
            "type": "string",
            "nullable": true
          },
          "CalendarUrl": {
            "type": "string",
            "nullable": true
          },
          "CompanyName": {
            "type": "string",
            "nullable": true
          },
          "CompanyLogoUrl": {
            "type": "string",
            "nullable": true
          },
        }
      }
    },
    "securitySchemes": {
      "jwt-rsa-custom-authorizer": {
        "type": "apiKey",
        "name": "Authorization",
        "in": "header",
        "x-amazon-apigateway-authtype": "custom",
        "x-amazon-apigateway-authorizer": {
          "authorizerUri": "[AUTHORIZER_URI]",
          "authorizerCredentials": "[AUTHORIZER_CREDENTIALS]",
          "authorizerResultTtlInSeconds": "[AUTHORIZER_RESULT_TTL_IN_SECONDS]",
          "identityValidationExpression": "^Bearer [-0-9a-zA-z\\.]*$",
          "type": "token"
        }
      }
    }
  }
}