diff --git a/src/plugins/presentation_util/README.mdx b/src/plugins/presentation_util/README.mdx
index 35b80e363453..575e8002e6eb 100755
--- a/src/plugins/presentation_util/README.mdx
+++ b/src/plugins/presentation_util/README.mdx
@@ -162,7 +162,7 @@ Once your services and providers are defined, and you have at least one set of f
 import { pluginServices } from './services';
 import { registry } from './services/kibana';
 
-  public async start(
+  public start(
     coreStart: CoreStart,
     startPlugins: StartDeps
   ): Promise<PresentationUtilPluginStart> {
diff --git a/x-pack/plugins/lists/server/plugin.ts b/x-pack/plugins/lists/server/plugin.ts
index 6a1b0733c186..7fa1bc460723 100644
--- a/x-pack/plugins/lists/server/plugin.ts
+++ b/x-pack/plugins/lists/server/plugin.ts
@@ -27,9 +27,7 @@ import { getUser } from './get_user';
 import { initSavedObjects } from './saved_objects';
 import { ExceptionListClient } from './services/exception_lists/exception_list_client';
 
-export class ListPlugin
-  implements Plugin<Promise<ListPluginSetup>, ListsPluginStart, {}, PluginsStart>
-{
+export class ListPlugin implements Plugin<ListPluginSetup, ListsPluginStart, {}, PluginsStart> {
   private readonly logger: Logger;
   private readonly config: ConfigType;
   private spaces: SpacesServiceStart | undefined | null;
@@ -40,7 +38,7 @@ export class ListPlugin
     this.config = this.initializerContext.config.get<ConfigType>();
   }
 
-  public async setup(core: CoreSetup): Promise<ListPluginSetup> {
+  public setup(core: CoreSetup): ListPluginSetup {
     const { config } = this;
 
     initSavedObjects(core.savedObjects);
@@ -70,7 +68,7 @@ export class ListPlugin
     };
   }
 
-  public start(core: CoreStart, plugins: PluginsStart): void {
+  public start(core: CoreStart, plugins: PluginsStart): ListsPluginStart {
     this.logger.debug('Starting plugin');
     this.security = plugins.security;
     this.spaces = plugins.spaces?.spacesService;
diff --git a/x-pack/plugins/monitoring/server/plugin.ts b/x-pack/plugins/monitoring/server/plugin.ts
index 3b939e736165..18eb8fd4d4dd 100644
--- a/x-pack/plugins/monitoring/server/plugin.ts
+++ b/x-pack/plugins/monitoring/server/plugin.ts
@@ -207,7 +207,7 @@ export class MonitoringPlugin
     }
   }
 
-  async start(coreStart: CoreStart, { licensing }: PluginsStart) {
+  start(coreStart: CoreStart, { licensing }: PluginsStart) {
     const config = this.config!;
     this.cluster = instantiateClient(
       config.ui.elasticsearch,
diff --git a/x-pack/test/functional_cors/plugins/kibana_cors_test/server/plugin.ts b/x-pack/test/functional_cors/plugins/kibana_cors_test/server/plugin.ts
index e6c3f4b05aab..9ba373c02faf 100644
--- a/x-pack/test/functional_cors/plugins/kibana_cors_test/server/plugin.ts
+++ b/x-pack/test/functional_cors/plugins/kibana_cors_test/server/plugin.ts
@@ -7,7 +7,6 @@
 
 import Hapi from '@hapi/hapi';
 import { kbnTestConfig } from '@kbn/test';
-import { take } from 'rxjs/operators';
 import Url from 'url';
 import abab from 'abab';
 
@@ -47,20 +46,18 @@ fetch('${url}', {
 
 export class CorsTestPlugin implements Plugin {
   private server?: Hapi.Server;
+
   constructor(private readonly initializerContext: PluginInitializerContext) {}
 
-  async setup(core: CoreSetup) {
+  setup(core: CoreSetup) {
     const router = core.http.createRouter();
     router.post({ path: '/cors-test', validate: false }, (context, req, res) =>
       res.ok({ body: 'content from kibana' })
     );
   }
 
-  async start(core: CoreStart) {
-    const config = await this.initializerContext.config
-      .create<ConfigSchema>()
-      .pipe(take(1))
-      .toPromise();
+  start(core: CoreStart) {
+    const config = this.initializerContext.config.get<ConfigSchema>();
 
     const server = new Hapi.Server({
       port: config.port,
@@ -78,8 +75,9 @@ export class CorsTestPlugin implements Plugin {
         return h.response(renderBody(kibanaUrl));
       },
     });
-    await server.start();
+    server.start();
   }
+
   public stop() {
     if (this.server) {
       this.server.stop();
diff --git a/x-pack/test/usage_collection/plugins/application_usage_test/public/plugin.ts b/x-pack/test/usage_collection/plugins/application_usage_test/public/plugin.ts
index b0c777593b02..ff1e89b58c7e 100644
--- a/x-pack/test/usage_collection/plugins/application_usage_test/public/plugin.ts
+++ b/x-pack/test/usage_collection/plugins/application_usage_test/public/plugin.ts
@@ -12,8 +12,12 @@ import './types';
 export class ApplicationUsageTest implements Plugin {
   public setup(core: CoreSetup) {}
 
-  public async start(core: CoreStart) {
-    const applications = await core.application.applications$.pipe(first()).toPromise();
-    window.__applicationIds__ = [...applications.keys()];
+  public start(core: CoreStart) {
+    core.application.applications$
+      .pipe(first())
+      .toPromise()
+      .then((applications) => {
+        window.__applicationIds__ = [...applications.keys()];
+      });
   }
 }