diff --git a/homeassistant/components/ecovacs/config_flow.py b/homeassistant/components/ecovacs/config_flow.py
index e19d9994f9e..2637dbbddf8 100644
--- a/homeassistant/components/ecovacs/config_flow.py
+++ b/homeassistant/components/ecovacs/config_flow.py
@@ -2,6 +2,7 @@
 
 from __future__ import annotations
 
+from functools import partial
 import logging
 import ssl
 from typing import Any
@@ -100,11 +101,14 @@ async def _validate_input(
     if not user_input.get(CONF_VERIFY_MQTT_CERTIFICATE, True) and mqtt_url:
         ssl_context = get_default_no_verify_context()
 
-    mqtt_config = create_mqtt_config(
-        device_id=device_id,
-        country=country,
-        override_mqtt_url=mqtt_url,
-        ssl_context=ssl_context,
+    mqtt_config = await hass.async_add_executor_job(
+        partial(
+            create_mqtt_config,
+            device_id=device_id,
+            country=country,
+            override_mqtt_url=mqtt_url,
+            ssl_context=ssl_context,
+        )
     )
 
     client = MqttClient(mqtt_config, authenticator)
diff --git a/homeassistant/components/ecovacs/controller.py b/homeassistant/components/ecovacs/controller.py
index c22fb240536..ec67845cf9f 100644
--- a/homeassistant/components/ecovacs/controller.py
+++ b/homeassistant/components/ecovacs/controller.py
@@ -3,6 +3,7 @@
 from __future__ import annotations
 
 from collections.abc import Mapping
+from functools import partial
 import logging
 import ssl
 from typing import Any
@@ -64,32 +65,28 @@ class EcovacsController:
         if not config.get(CONF_VERIFY_MQTT_CERTIFICATE, True) and mqtt_url:
             ssl_context = get_default_no_verify_context()
 
-        self._mqtt = MqttClient(
-            create_mqtt_config(
-                device_id=self._device_id,
-                country=country,
-                override_mqtt_url=mqtt_url,
-                ssl_context=ssl_context,
-            ),
-            self._authenticator,
+        self._mqtt_config_fn = partial(
+            create_mqtt_config,
+            device_id=self._device_id,
+            country=country,
+            override_mqtt_url=mqtt_url,
+            ssl_context=ssl_context,
         )
+        self._mqtt_client: MqttClient | None = None
 
         self._added_legacy_entities: set[str] = set()
 
     async def initialize(self) -> None:
         """Init controller."""
-        mqtt_config_verfied = False
         try:
             devices = await self._api_client.get_devices()
             credentials = await self._authenticator.authenticate()
             for device_config in devices:
                 if isinstance(device_config, DeviceInfo):
                     # MQTT device
-                    if not mqtt_config_verfied:
-                        await self._mqtt.verify_config()
-                        mqtt_config_verfied = True
                     device = Device(device_config, self._authenticator)
-                    await device.initialize(self._mqtt)
+                    mqtt = await self._get_mqtt_client()
+                    await device.initialize(mqtt)
                     self._devices.append(device)
                 else:
                     # Legacy device
@@ -116,7 +113,8 @@ class EcovacsController:
             await device.teardown()
         for legacy_device in self._legacy_devices:
             await self._hass.async_add_executor_job(legacy_device.disconnect)
-        await self._mqtt.disconnect()
+        if self._mqtt_client is not None:
+            await self._mqtt_client.disconnect()
         await self._authenticator.teardown()
 
     def add_legacy_entity(self, device: VacBot, component: str) -> None:
@@ -127,6 +125,16 @@ class EcovacsController:
         """Check if legacy entity is added."""
         return f"{device.vacuum['did']}_{component}" in self._added_legacy_entities
 
+    async def _get_mqtt_client(self) -> MqttClient:
+        """Return validated MQTT client."""
+        if self._mqtt_client is None:
+            config = await self._hass.async_add_executor_job(self._mqtt_config_fn)
+            mqtt = MqttClient(config, self._authenticator)
+            await mqtt.verify_config()
+            self._mqtt_client = mqtt
+
+        return self._mqtt_client
+
     @property
     def devices(self) -> list[Device]:
         """Return devices."""